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NATIONAL PARK SERVICE 

RESEARCH/RESOURCES MANAGEMENT REPORT SER-71 

i-pt** LIBRARY 

The Southern Appalachian Spruce -Fir Ecosystem: 
Its Biology and Threats 




United States Department of the Interior 

National Park Service 
Southeast Region 

DATE: Ikl 



The Research/Resources Management Series of the Natural Science and 
Research Division, National Park Service, Southeast Regional Office, is 
the established in-house medium for distributing scientific information 
to park Superintendents, resource management specialists, and other 
National Park Service personnel in the parks of the Southeast Region. 
The papers in the Series also contain information potentially useful to 
other Park Service areas outside the Southeast Region and may benefit 
external (non-NPS) researchers working within units of the National Park 
System. The Series provides for the retention of research information in 
the biological, physical, and social sciences and makes possible more 
complete in-house evaluation of internal research, technical, and 
consultant reports. 

The Series includes: 

1. Research reports which directly address resource management 
problems in the parks. 

2. Papers which are primarily literature reviews and/or 
bibliographies of existing information relative to park 
resources or resource management problems. 

3. Presentations of basic resource inventory data. 

4. Reports of contracted scientific research studies funded 
or supported by the National Park Service. 

5. Other reports and papers considered compatible to the Series, 
including results of applicable university or independent 
research relating to the preservation, protection, and 
management of resources administered by the National Park 
Service. 



Southeast Regional Research/Resources Management Reports are produced by 
the Natural Science and Research Division, Southeast Regional Office. 
Copies may be obtained from: 

National Park Service 

Southeast Regional Office 

Natural Science and Research Division 

75 Spring Street, S.W. 

Atlanta, Georgia 30303 



NOTE: Use of trade names does not constitute or imply U.S. Government 
endorsement of commercial products. 






THE SOUTHERN APPALACHIAN SPRUCE-FIR ECOSYSTEM: 
ITS BIOLOGY AND THREATS 



Edited by Peter S. White 



NATIONAL PARK SERVICE - Southeast Region 
Research/Resources Management Report SER-71 



3q /k 

APR 1 2 19B5 



Uplands Field Research Laboratory 
Great Smoky Mountains National Park 
Gatlinburg, Tennessee 37738 



November 1984 



UNITED STATES DEPARTMENT OF THE INTERIOR 
NATIONAL PARK SERVICE 




LIBRARY 

GREAT S^OKY MO 
KtfiONAL PnhX 



White, P. S. 1984. The Southern Appalachian Spruce-Fir Ecosystem: 
Its Biology and Threats. U.S. Department of the Interior, 
National Park Service, Research/Resources Management Report 
SER-71. 268 pp. 



ii 



Foreword 

The southernmost spruce-fir forests of eastern North America 
occur in the high peaks region of the southern Appalachians, from 
southwestern Virginia to eastern Tennessee and western North 
Carolina. These forests are unique and imperiled. The dominant 
trees of this ecosystem type are subject to threats. Fraser fir, 
a narrow southern Appalachian endemic, is directly threatened by 
an introduced insect (Eagar, DeSelm and Boner, this volume). It 
has been conjectured that a dramatic decline in red spruce radial 
increment has been caused by air pollution. Within the next 
several decades the dramatic alteration of the last old growth 
stands of this ecosystem type will occur. 

The importance of southern Appalachian spruce-fir resides in 
several properties: though related to northern spruce-fir 
vegetation, it is biologically unique (White, this volume); it is 
a geographically restricted type (White, Pittillo, Saunders, this 
volume); it supports populations of rare plants (White, Pittillo, 
Dey, Smith, Petersen, this volume) and animals (Linzey, Pelton, 
Mathews and Echternacht, Rabenold, this volume); it dominates the 
headwaters of mountain streams and influences downstream water 
quality and fisheries; and it is aesthetically important to 
recreational users (Saunders, this volume) . The National Park 
Service manages two areas that include examples of the spruce-fir 
ecosystem: Great Smoky Mountains National Park (an International 
Biosphere Reserve and World Heritage Site) and the Blue Ridge 
Parkway. Great Smoky Mountains National Park contains the 
largest existing tract of southern Appalachian spruce-fir. 

Between 1960 and the mid-1970s, the primary cause for 
concern about southern Appalachian spruce-fir was the spread of 
the introduced insect, the balsam woolly aphid (Eagar, DeSelm and 
Boner, this voume) . This pest will probably eliminate mature 
Fraser fir trees within the next several decades and may 
eventually cause the extirpation of this southern Appalachian 
endemic species. Only Fraser fir on Mt. Rogers seems to be 
resistant (see Rheinhardt, this volume) . Loss of Fraser fir will 
effect the rest of the biota of the spruce-fir forests, 
including, for example, lichens that inhabit fir bark and 
branches (Dey, this volume) , amphibians effected by stand 
microclimate (Mathews and Echternacht, this volume) , and 
understory herbs effected by increased insolation. With the 
production of large amounts of organic debris and the 
successional replacement of the fir trees, the effects of the 
balsam woolly aphid will ramify through this ecosystem. 

In the past decade another concern has been raised: 
atmospheric deposition of pollutants. Red spruce has undergone a 
dramatic reduction in annual radial increment, starting as early 
as 1957 (S. McLaughlin, unpublished data from the FORAST 
project) . The data documenting this sudden shift in vigor have 
not been fully published; in addition, more data are now being 
collected. Hence, it is premature to judge how widespread the 
growth decline is and how it is related to site factors (like 



111 



elevation) , tree age, and stand history. It is also unclear at 
this time whether the growth decline results in increased spruce 
mortality in the southern Appalachians, but studies in Vermont 
have substantiated heavy (>60 percent of canopy stems) , recent, 
and unexplained mortality in northern red spruce populations. 

Speculation about the causes of the spruce decline center on 
pollutant deposition. Pollutant deposition is known to be 
significant in the mountainous terrain of the eastern US. 
Further, though circumstantial, cause for concern is the 
devastation of high elevation coniferous forests in Western 
Europe over the last five years — research has shown a strong 
connection to pollutant deposition there. Whatever the cause of 
red spruce decline, substantial pollutant deposition is occurring 
in the southern mountains (Lovett, Bogle and Turner, this 
volume) . The gases and precipitation borne materials that are 
pervading this ecosystem are likely to cause effects on several 
levels of biological organization and underscore the importance 
of ecosystem level research. Predicting these changes will be 
hampered by the current lack of knowledge about the functioning 
of this ecosystem. 

Because of the biological importance and immediacy of the 
threats to this ecosystem, the spruce-fir zone has received 
increasing research attention. Scientists from the National Park 
Service, Oak Ridge National Lab, the Tennessee Valley Authority, 
the Forest Service, North Carolina State University, the 
University of Tennessee, Virginia Polytechnic Institute, and 
other regional institutions have begun research projects to 
assess the spruce-fir ecosystem and pollutant deposition. These 
studies range from baseline data collection on permanent plots to 
detailed analysis of ecological processes on intensive study 
sites and laboratory experiments to assess pollutant sensitivity 
of component species. This research will make possible a more 
complete understanding of the state and trajectory of the spruce- 
fir ecosystem, and the effects of pollutants, over the next 2 to 
5 years. 

In order to assess the data base at the beginning of this 
research effort, Uplands Field Research Lab, a National Park 
Service research station in Great Smoky Mountains National Park, 
held a symposium entitled, "The southern Appalachian spruce-fir 
ecosystem: status, threats, and management". The goals of this 
symposium were to summarize the state of our knowledge about the 
spruce-fir ecosystem, to describe its threats, to assess the 
quality of the data bases for long term understanding of the 
changes that are taking place, to discuss management issues, to 
identify key research areas, and to promote institutional 
cooperation in the research effort. We specifically addressed the 
following questions: How will we be able to detect and evaluate 
change at the population, community, and ecosystem levels? Will 
we be able to predict extinction risk for vulnerable species? 
How will we predict the future state of this ecosystem? This 
volume presents the results of that meeting. 



IV 



This volume is organized as follows. After a general 
introduction to the spruce-fir ecosystem (White) , the 
paleoecological history of this vegetation is described (Delcourt 
and Delcourt) . This is followed by a summary of the interaction 
of balsam woolly aphid and Fraser fir (Eagar) and a description 
of stand changes after balsam woolly aphid infestation (DeSelm 
and Boner) . Next the geographic areas of spruce-fir are 
described in chapters on the Blue Ridge (Pittillo) and southwest 
Virginia (Rheinhardt) . The next two chapters deal with 
recreational impacts (Saunders) and logging history (Pyle) . 
These chapters are followed by seven chapters describing 
particular groups of organisms: mosses (Smith) , lichens (Dey) , 
fungi (Petersen) , herpetofauna (Mathews and Echternacht) , 
avifauna (Rabenold) , and mammals (Pelton, Linzey) . Notable by 
its absence in this section of the proceedings is an important 
group for which little data exist: soil organisms. An outline 
of soil types of the spruce-fir zone (Springer) is followed by a 
detailed analysis of lead in vegetation and soils (Bogle and 
Turner) . The final chapter (Lovett) describes the potential for 
high amounts of pollutant deposition in mountainous terrain. We 
have also prepared two Appendices: Appendix I gives an annotated 
checklist of the vascular plants of southern Appalachian spruce- 
fir and Appendix II presents a bibliography of research on 
southern Appalachian spruce-fir vegetation. 

The National Park Service protects the most significant 
tract of undisturbed southern Appalachian spruce-fir forest 
(located in Great Smoky Mountains National Park) . Additional NPS 
spruce-fir stands are found along the Blue Ridge Parkway. NPS is 
committed to maintaining and protecting natural ecosystems and 
their processes. Further, the role of Great Smoky Mountains 
National Park in the International Biosphere Reserve program 
supports NPS biologists and managers in their work on this 
threatened ecosystem. 

The opinions of the authors of the several chapters in this 
volume do not necessarily reflect the views of the National Park 
Service. I would like to take this opportunity to thank the 
authors for their hard work and long patience as this volume was 
assembled. 



P. White 

Uplands Field Research Laboratory 

Great Smoky Mountains National Park 



TABLE OF CONTENTS 

Page 

FOREWORD iii 

LIST OF CONTRIBUTORS viii 

LIST OF OTHER PARTICIPANTS x 

SOUTHERN APPALACHIAN SPRUCE-FIR, AN INTRODUCTION 

P. S. White 1 

LATE-QUATERNARY HISTORY OF THE SPRUCE-FIR ECOSYSTEM IN THE 
SOUTHERN APPALACHIAN MOUNTAIN REGION 

H. R. Delcourt and P. A. Delcourt 22 

REVIEW OF THE BIOLOGY AND ECOLOGY OF THE BALSAM WOOLLY APHID 
IN SOUTHERN APPALACHIAN SPRUCE-FIR FORESTS 

C. Eagar 36 

UNDERSTORY CHANGES IN SPRUCE-FIR DURING THE FIRST 16-20 YEARS 
FOLLOWING DEATH OF THE FIR 

H.R. DeSelm and R. R. Boner 51 

REGIONAL DIFFERENCES OF SPRUCE-FIR FORESTS OF THE SOUTHERN 
BLUE RIDGE SOUTH OF VIRGINIA 

J. D. PittillO 70 

COMPARATIVE STUDY OF COMPOSITION AND DISTRIBUTION PATTERNS 
OF SUBALPINE FORESTS IN THE BALSAM MOUNTAINS OF SOUTHWEST 
VIRGINIA AND THE GREAT SMOKY MOUNTAINS 

R. D. Rheinhardt 87 

RECREATIONAL IMPACTS IN THE SOUTHERN APPALACHIAN SPRUCE-FIR 
ECOSYSTEM 

P. R. Saunders 100 

PRE-PARK DISTURBANCE IN THE SPRUCE-FIR FORESTS OF GREAT 
SMOKY MOUNTAINS NATIONAL PARK 

C. Pyle 115 

A STATUS REPORT ON BRYOPHYTES OF THE SOUTHERN APPALACHIAN 
SPRUCE-FIR FORESTS 

D. K. Smith 131 

LICHENS OF THE SOUTHERN APPALACHIAN MOUNTAIN SPRUCE-FIR ZONE 
AND SOME UNANSWERED ECOLOGICAL QUESTIONS 

J. P. Dey 139 

CURRENT KNOWLEDGE OF SPRUCE-FIR FUNGI 

R. Petersen 151 



VI 



HERPETOFAUNA OF THE SPRUCE-FIR ECOSYSTEM IN THE SOUTHERN 
APPALACHIAN MOUNTAIN REGION, WITH EMPHASIS ON GREAT 
SMOKY MOUNTAINS NATIONAL PARK 

R. C. Mathews, Jr., and A. C. Echternacht 155 

BIRDS OF APPALACHIAN SPRUCE-FIR FORESTS: DYNAMICS OF 
HABITAT-ISLAND COMMUNITIES 

K. N. Rabenold 168 

MAMMALS OF THE SPRUCE-FIR FOREST IN GREAT SMOKY MOUNTAINS 
NATIONAL PARK 

M. R. Pelton 187 

DISTRIBUTION AND STATUS OF THE NORTHERN FLYING SQUIRREL AND 
THE NORTHERN WATER SHREW IN THE SOUTHERN APPALACHIANS 

D. W. Linzey 193 

SOILS IN THE SPRUCE-FIR REGION OF THE GREAT SMOKY MOUNTAINS 

M. E. Springer 201 

LEAD IN VEGETATION, FOREST FLOOR MATERIAL, AND SOILS OF 
THE SPRUCE-FIR ZONE, GSMNP 

M. A. Bogle and R. R. Turner 211 

POLLUTANT DEPOSITION IN MOUNTAINOUS TERRAIN 

G. M. Lovett 225 

APPENDIX I. VASCULAR PLANTS OF SOUTHERN APPALACHIAN 
SPRUCE-FIR: ANNOTATED CHECKLISTS ARRANGED BY HABITAT, 
GROWTH FORM, AND GEOGRAPHICAL RELATIONSHIPS 

P. S. White and L. A. Renfro 235 

APPENDIX II. BIBLIOGRAPHY OF RESEARCH ON SOUTHERN APPALACHIAN 
SPRUCE-FIR VEGETATION 

P. S. White and C. Eagar 247 



vn 



LIST OF CONTRIBUTORS 



M. A. Bogle 

Environmental Sciences Division 

Oak Ridge National Lab 

Oak Ridge, TN 37830 

R. R. Boner 

The Nature Conservancy 

Minneapolis, MN 



Hazel Delcourt 

Depts. of Geology and Botany 
University of Tennessee 
Knoxville, TN 37738 

Paul Delcourt 
Dept. of Geology 
University of Tennessee 
Knoxville, TN 37996-1100 

H. R. DeSelm 
Dept. of Botany 
University of Tennessee 
Knoxville, TN 37996-1100 

John Dey 

Biology Dept. 

Illinois Wesleyan University 

Bloomington, IL 61701 

Christopher Eagar 
Uplands Field Research Lab 
Great Smoky Mountains Nat'l Prk 
Gatlinburg, TN 37738 

A. C. Echternacht 
Dept. of Zoology 
University of Tennessee 
Knoxville, TN 37996-1100 

Donald W. Linzey 
2101 Nellies Cove Rd 
Blacksburg, VA 24060 



Gary Lovett 

Environmental Science Division 
Oak Ridge National National Lab 
Oak Ridge, TN 37830 



M. R. Pelton 

Forestry, Fisheries, and Wildlife 
University of Tennessee 
Knoxville, TN 37901-1071 

R. Petersen 
Dept. of Botany 
University of Tennessee 
Knoxville, TN 37996-1100 

J. Dan Pittillo 

Dept. of Biology 

Western Carolina University 

Cullowhee, NC 28723 

Richard D. Rheinhardt 
305 N. Boundary St. 
Williamsburg, VA 23185 



Charlotte Pyle 

Uplands Field Research Lab 

Great Smoky Mountains National Park 

Gatlinburg, TN 37738 

K. N. Rabenold 

Department of Biological Sciences 

Purdue University 

West Lafayette, IN 47907 

L. A. Renfro 

Uplands Field Research Lab 

Great Smoky Mountains National Park 

Gatlinburg, TN 37738 

P. R. Saunders 
Forest and Range Management 
Washington State University 
Pullman, WA 99164-6410 

D. K. Smith 
Dept. of Botany 
University of Tennessee 
Knoxville, TN 37996-1100 

Max Springer 

1600 Autry Way Laboratory 

Knoxville, TN 37919 



vm 



CONTRIBUTORS, CONTINUED: 



R. C. Mathews, Jr. 

Geo-Marine, Inc. 

Engineering and Environmental Services 

1316 Fourteenth St. 

Piano, Texas 75074 

R. R. Turner 

Environmental Sciences Division 

Oak Ridge National Lab 

Oak Ridge, TN 37830 

Peter S. White 

Uplands Field Research Lab 

Great Smoky Mountains National Park 

Gatlinburg, TN 37738 



IX 



OTHER WORKSHOP PARTICIPANTS 



Frank Arthur 

Dept. of Entomology 

North Carolina State University 

Raleigh, NC 27650 

Fred Baes 

Environmental Sciences Division 

Oak Ridge National Lab 

Oak Ridge, TN 37830 

Larry Barden 

Biology Dept. 

University of North Carolina 

Charlotte, NC 28213 

Edward Buckner 

Forestry, Fisheries and Wildlife 
University of Tennessee 
Knoxville, TN 37901-1071 

E. E. C. Clebsch 
Department of Botany 
University of Tennessee 
Knoxville, TN 37996-1100 

Jean L. Davidson 
Dept. of Geology 
University of Tennessee 
Knoxville, TN 37996-1100 

Paula DePriest 
Dept. of Botany 
University of Tennessee 
Knoxville, TN 37996-1100 

Leroy Fox 

4116 Jomandowa Lane 

Knoxville, TN 37919 

Doug Holland 
Plant and Soil Science 
University of Tennessee 
Knoxville, TN 37996-1100 

Dale Johnson 

Environmental Sciences Division 

Oak Ridge National Lab 

Oak Ridge, TN 37830 

Richard Lancia 

Forestry Dept. 

North Carolina State University 

Raleigh, NC 27650 



D. A. Lietzke 

Plant and Soil Science Dept. 
University of Tennessee 
Knoxville, TN 37901-1071 

John D. McKrone 

Dean, School of Arts and Sciences 
Western Carolina University 
Cullowhee, NC 28723 

S. B. McLaughlin 
Environmental Sciences Division 
Oak Ridge National Lab 
Oak Ridge, TN 37830 

Don McLeod 
Dept. of Biology 
Mars Hill College 
Mars Hill, NC 28754 

Niki Nicholas 

Uplands Field Research Lab 

Great Smoky Mountains National Par 

Gatlinburg, TN 37738 

Jerry Olson 

Environmental Sciences Division 

Oak Ridge National Lab 

Oak Ridge, TN 37830 

Nancy Reagan 

Western Carolina University 

Cullowhee, NC 28723 

David Sackett 
Dept. of Geology 
University of Tennessee 
Knoxville, TN 37916 

David Shafer 
Dept. of Geology 
University of Tennessee 
Knoxville, TN 37916 

Alan Smith 
Dept. of Biology 
Mars Hill College 
Mars Hill, NC 28754 



THE SOUTHERN APPALACHIAN SPRUCE-FIR ECOSYSTEM, 

AN INTRODUCTION 

Peter S. White 1 

Abstract. — Southern Appalachain spruce-fir is a 
distinctive variant within the complex of North American 
forests dominated by Picea (spruce) and Abies (fir) . 
Because of the geography and topography of the region, 
spruce-fir forests in the south are isolated from related 
northern vegetation and occur as a series of island-like 
stands at high elevations. These areas are rich in 
endemics and in rare plants and animals. The integrity 
of Southern Appalachian spruce-fir is threatened by an 
exotic insect pest, the balsam woolly aphid, and by 
atmospheric deposition of pollutants. The balsam woolly 
aphid will eliminate mature Abies f raseri (Fraser fir) 
trees from most of its range within the next several 
decades. Pollutant deposition has been implicated in the 
recent radial increment suppression in Picea rubens (red 
spruce) and is probably causing other ecosystem changes 
as well. Ecosystem oriented research is a key to 
understanding the role of pollutant deposition in these 
forests. Previous ecosystem work included 
characterization of stand biomass, nutrient pools, 
productivity, and discussion of nutrient cycling trends. 
Ongoing research in Great Smoky Mountains National Park, 
which contains the largest existing area of southern 
Appalachian spruce-fir, is directed at a variety of 
levels from physiological response in trees to change at 
the population, community, and ecosystem levels. Logging 
and fire between 1880 and 1930 removed about 50 percent 
of the total area of southern Appalachian spruce-fir; the 
last undisturbed stands of this ecosystem type will 
probably have been dramatically altered in the next 
several decades. 

Additional keywords : Abie s f raseri f ecosystem processes, 
monitoring, Picea rubens . rarity, southern Appalachian 
vegetation, threats to ecosystems 

INTRODUCTION 

The southernmost spruce-fir forests in eastern North America 
occur on the high peaks of the southern Appalachians in North 
Carolina and Tennessee (about Latitude 35 degr. N; Ramseur 1960, 
Pittillo, Rheinhardt, Saunders, this volume). The biological 
importance of these forests and the factors that threaten the 
integrity of this ecosystem are the subject of this volume. The 
goals of this chapter are to define southern Appalachian spruce- 
fir as a distinctive variant of North American spruce-fir 
forests, to show the isolation and restricted extent of this 

^Research biologist, Uplands Field Research Laboratory, Great 
Smoky Mountains National Park, Gatlinburg, TN 37738 



ecosystem, to present an overview of the threats that are now 
present, and to review characteristics of this ecosystem that are 
not specifically treated in other chapters (conservation status 
and ecosystem processes) . I will also outline current research 
in the spruce-fir forests of Great Smoky Mountains Natinal Park, 
which contains the largest single tract of southern Appalachian 
spruce-fir, including important old growth stands. 

SOUTHERN APPALACHIAN SPRUCE-FIR: 
DEFINITION AND CONTRASTS WITH NORTHERN SPRUCE-FIR 

Physiognomy and floristic s. Forests dominated by spruce 
(Picea) and fir ( Abies ) characterize a broad region of North 
America, from Alaska to the eastern Provinces of Canada. In the 
east, spruce-fir forests are also found southward along the 
Appalachian mountain chain. Southern Appalachian spruce-fir is 
physiognomically very similar to northern Appalachian spruce- 
fir. Both southern and northern Appalachian spruce-fir are 
dominated by needle-leaved, evergreen, conifers, and have 
conspicuous bryophyte layers (Oosting and Billings 1951) . The 
most distinctive physiognomic differences between northern and 
southern Appalachian old growth spruce-fir stands are (1) the 
greater average height and faster growth rates of trees in the 
south, (2) the greater herb and bryophyte cover in the south, and 
(3) the occurrence of an evegreen, broad-leaved shrub layer 
(principally, Rhod odendron catawbiense) in southern stands on 
ridges and steep and rocky slopes (Oosting and Billings, 1951, 
Whittaker 1956, Crandall 1958). Species richness in all strata 
is similar in southern compared to northern stands (Oosting and 
Billings 1951) . 

Because of this physiognomic similarity and because a number 
of genera and species are found in both southern and northern 
areas, southern Appalachian spruce-fir is sometimes referred to 
as "northern" or "boreal" vegetation. This usage, however, 
obscures the unique characteristics of Appalachian spruce-fir in 
general and the southern variant of this vegetation in 
particular. "Boreal" spruce-fir is, properly, the broad, 
predominantly low elevation, vegetation of high latitudes. The 
characteristic boreal spruces are Picea glauca (white spruce) and 
Picea mariana (black spruce) (La Roi 1967, Larsen 1980) . The 
spruce of the Appalachians is Pice a rubens (red spruce); it is 
the predominant spruce species in the northern Appalachians and 
the sole species in the south. While Abies balsamea (balsam fir) 
is the fir species of both boreal and northern Appalachian 
spruce-fir, it is replaced by the narrow endemic Abies f raseri 
(Fraser fir) in the southern high peaks region. Thus the two 
southern Appalachian dominants, Picea ruben s and Abies f raseri f 
are Appalachian montane, rather than boreal, species. 

There are other floristic differences as well — Betula 
cordifolia (heart-leaved paper birch) , although rare in the 
south, is an Appalachian, humid region, species, while Betula 
papyrifera (paper birch) is the boreal forest white birch. While 
Betula lutea is common in the lower elevation part of northern 



Appalachian spruce-fir, it is the only birch to achieve 
importance in southern stands (Oosting and Billings 1951) . 
Additional species are characteristic of boreal forest (e.g., 
Pinus banksian a, Popul us balsamifera ) , northern Appalachian 
spruce-fir (e.g., Sorbus decora, Solidag o macrophylla) , or 
southern Appalachian spruce-fir (e.g., Vaccinium erythrocarpon . 
Menziesia p ilos a) (White 1976) . Endemism is especially marked 
in the south (Pittillo, Appendix I, this volume; Oosting and 
Billings 1951, Ramseur 1960, Holt 1970, White 1976). 

One hundred and thirty-two vascular plant species are found 
in GRSM spruce-fir forests (Appendix I) . Of these, 46 are 
reasonably characteristic of this forest type. Of this total, 73 
percent are found in both northern and southern Appalachian 
spruce-fir, and 27 percent are found in southern Appalachian 
spruce-fir only. Eight species (17 percent of the species 
characteristic of southern Appalachian spruce-fir) are endemic to 
the southern Appalachian high peaks: Abies f raseri , Ri bes 
rotundifolium P Vaccinium erythrocarpon , Angelica triqui nata . 
Aster chlo rolepis , Cacal ia rugelia, Houstonia ser pyllifolia , and 
Solidago glomerata. By contrast, eighteen species absent from 
southern Appalachian spruce-fir are characteristic of northern 
Appalachian spruce-fir (Appendix I) . Examples are: Sorbus 
decora. Chio genes hispidula . Nemopanthu s mucronata, Coptis 
groenland ica, Cor nus canadensis , Pyrola spp. . Solidag o 
macr o phylla , and Tri entalis borealis . 

Floristic boundaries are not, of course, discrete between 
the three kinds of spruce-fir, but the unique features of 
southern spruce-fir argues against the use of the term "boreal" 
for this vegetation. More appropriate terms in the literature 
are "subalpine" (borrowed from western mountains where spruce-fir 
occurs below alpine vegetation — this is also true in the higher 
New England mountains) and "montane" for the Appalachian spruce- 
fir type (White 1976) . The simplest and most straightforward 
designation in the south remains "southern Appalachian spruce- 
fir" and it is the one which is used here. The southern spruce- 
fir vegetation is related to northern vegetation types, but 
it is a distinct variant within the complex of North American 
Picea-Abies dominated ecosystems. 

Elevation gradients. The change in forest compostion along 
the elevational gradient is also similar between northern and 
southern Appalachian spruce-fir. In New England, there is a 
continuum from Fag us -A cer-Be tula forests (northern hardwoods) to 
Picea-Be t ul a, Picea-A bie s . and Abies types (Siccama 1974) . Picea 
ranges to lower elevations than Abies . where it is scattered in 
the northern hardwood forest or occurs as a local dominant on 
steep slopes and ridges. Betula lutea ranges to higher 
elevations than either Acer s accharum or F agus and is especially 
prominent in the northern hardwood-spruce-fir interface. The 
same overall pattern occurs in the south, with Picea ranging to 
lower elevations, Abies increasing in importance with elevation, 
and Betula lutea being especially prominent at the hardwood 
interface (Whittaker 1956) . However, there are also differences: 



Tsuga i s prominent at the lower boundary of spruce-fir on some 
slopes in the south and the spruce-fir zone sometimes ajoins 
communities other than northern hardwoods (e.g., communities 
dominated by Ouercus rubra; Whittaker 1956) . Within the 
northern hardwood community itself are several species absent 
from the northern Appalachians ( Aesculus octandra f Halesia 
Carolin a: Schofield 1958) . 

Average height and biomass of spruce-fir decline on two 
gradients: from low to high elevations and from moist (coves) to 
dry (ridges) sites (Whittaker 1956, 1966; Oosting and Billings 
1951) . The largest red spruce trees are found towards lower 
elevations and moister sites. There may also be a faster canopy 
turnover rate on ridges due to increased windthrow of trees. 
The gradients that control stand characteristics must be 
considered in the sampling design for testing hypotheses about 
ecosystem change. 

In both northern and southern Appalachian spruce-fir, the 
ecotone between spruce-fir and hardwood dominance is relatively 
abrupt. Investigations of this boundary have found that the 
species distribution fits the continuum model of vegetation 
change, but that the rate of vegetation change with elevation is 
greater across the boundary than on either side of it (Siccama 
1974, White 1976, Schofield 1958). The continuous nature of the 
vegetation change, however, means that the exact placement of the 
elevational ecotone is subjective. For example, Saunders (this 
volume) defines spruce-fir as relatively pure Abies and Picea 
dominance on all (convex and concave) sites, while Pyle (this 
volume) has used a definition which encompasses the spruce 
ridges, which descend to lower elevations than the vegetation 
type as a whole, and the spruce-yellow birch type. The result is 
that Pyle's and Saunders' estimates of the elevation of the 
spruce-fir-northern hardwood ecotone and of total spruce-fir area 
differ. Thus, no selection of a representative ecotone elevation 
is complete without reference to whether that boundary 
encompasses spruce-birch, spruce-hemlock, or other vegetation 
types. Further, reference must be made to the amount of 
landscape dominance accepted as above that ecotone (all sites, 
ridges but not coves, etc.). 

Natural stand dynamics. A recent study of natural 
disturbance regimes suggested that dynamics of southern 
Appalachian spruce-fir are dominated by spatially small wind- 
caused treefalls (White et al., in press). Larger disturbance 
patches seem more important in northern Appalachian spruce-fir 
(Reiners and Lang 1979, Foster and Reiners 1983), but this 
conclusion is tentative since the northern studies did not 
rigorously define the age of disturbance patches recognized and 
recent spruce mortality is a complicating factor there (Foster 
and Reiners 1983) . In the relatively pure Abies forests of high 
elevations in the northern Appalachians, Sprugel (1976) described 
the narrow bands of fir dieback called "fir waves". These waves 
are oriented perpendicular to slope gradients and progress 
upslope at about 2-5 m per yr (Sprugel 1976) . Patchwise blowdown 



of Fraser fir occurs on the highest summits of the southern 
Appalachians, but these lack the regularity and orientation of 
the northern fir waves. They are more like the fir patches 
described by Reiners and Lang (1979) for the northern 
Appalachians than they are like the true fir waves. 

A difference between montane (both southern and northern) 
and boreal spruce-fir is the role of fire. Humidity increases 
eastward within the boreal spruce-fir forest; in more continental 
areas westward, fire is an important natural disturbance and 
occurs on rotations of 50-200 years (Heinselman 1981) . Natural 
fire is much less important in the Appalachains , with fire 
rotations estimated as 500-1000 years in New England (Fahey and 
Reiners 1981) and even longer than this in the southern 
Appalachians (Harmon 1981) . The predominance of spatially small 
natural disturbances in the south means that current human- 
initiated disturbance introduces a new spatial scale into 
vegetation dynamics. The same could not be said of the northeast 
where several natural disturbances (e.g., the native spruce 
budworm) cause large disturbance patches. 

Enviro nment . The climate of southern Appalachian spruce-fir 
differs in several ways from northern Appalachian spruce-fir 
(Oosting and Billings 1951, Shanks 1954, Stephens 1969, White 
1976) . Climate varies from low to high elevations in both 
southern and northern areas; the data that are cited below 
should be taken as representative of the mid-point of this 
gradient. The frost free season within the spruce-fir zone is 
longer in the south (ca. 120-160 days) compared to the north (ca. 
100 days or less) , minimum winter temperatures are less severe 
(the mean minimum temperature for the coldest month is about -5 
degr. C. in the south, -20 degr. C. in the north), rainfall is 
higher (ca. 200 cm per yr in the south, 150 cm per yr in the 
north) , less precipitation falls as snow (<150 cm in the south, 
>400 cm in the north), himidity is higher, and photoperiod is 
shorter in summer and longer in winter than in the north. The 
less drastic winter temperatures have, in fact, been offered as 
an explanation for the observation that the balsam woolly aphid 
has proved to be an unimportant pest in the north, compared to 
the south, but biological differences between Fraser fir and 
balsam fir are also involved (Eager, this volume). The longer 
growing season has been advanced as an explanation for the fact 
that spruce and fir reach larger dimensions, higher growth rates, 
and longer lifespans in the south compared to the north (Oosting 
and Billings 1951). In fact, the best growth of red spruce is 
obtained both at its southern range limit and, within southern 
stands, at its lowest elevation limit. 

The disequilibrium hypoth esis . Spruce-fir is absent or 
poorly developed en some southern Appalachian slopes that reach 
seemingly appropriate elevations. Examples are the abrupt 
western boundary of spruce-fir in the Great Smoky Mountains 
(Whittaker 1956) and the absence of Abies f ra seri from Whitetop 
in southwestern Virginia (Rheinhardt, this volume). Whittaker 
(1956) hypothesized that this phenomenon was the result of 



historic factors: according to his theory, spruce-fir was 
restricted to elevations above 5700 ft (1740 m) during the 
warmest post-glacial times some 5,000 yr before present (Delcourt 
and Delcourt, this volume) . If insufficient area was available 
above this elevation on a particular mountain, spruce-fir became 
extinct as a vegetation type and rates of extinction were high 
for species characteristic of the high elevations. This scenario 
may underlie patchiness of high elevation species in the southern 
Appalachians (Ramseur 1960) and the strong relationship between 
the numbers of rare plants found on mountain areas and the size 
and maximum elevation of those areas (White et al. 1984, White 
and Miller, unpublished data) . According to this view, the 
distribution of spruce-fir as a vegetation type and its 
associated species are not fully in equilibrium with environment 
and the approach to equilibrium is limited by plant dispersal. 

The patchy distribution of plants in the region is 
illustrated by the presence of local endemics. For example, the 
flora of GRSM contains three vascular plants narrowly endemic to 
the park ( Cacali a rugelia , Calamagrosti s c ain ii . and G lyceria 
nubigena — see White and Wof ford 1984) ; these occur within or 
adjacent to the spruce-fir zone. Cacali a in particular has an 
enigamatic distribution: it is a frequent throughout high 
elevation forests of the Great Smoky Mountains but occurs nowhere 
outside this range. Roan Mountain contains several narrow 
endemics as well (e.g., Housto nia montana: Paul Somers, 
unpublished data) . 

The disequilibrium hypothesis should be used with caution, 
however. Southern Appalachian spruce-fir regenerated very poorly 
after logging and slash fires (Saunders, Pyle, this volume) and 
is absent from some areas due to this past human disturbance. 

THE ISOLATION AND ISLAND-LIKE NATURE 
OF SOUTHERN APPALACHIAN SPRUCE-FIR 

The latit ude-elevation relationship. Two edaphic kinds of 
spruce-fir vegetation occur along the Appalachian mountain chain: 
spruce-fir of mountain slopes (freely drained, upland sites) and 
spruce-fir of swamps and bogs (poorly drained, lowland sites) . 
The latter type is scarce southward, but becomes frequent on 
glaciated lands northward. I will discuss only the upland 
spruce-fir type here. 

While spruce-fir occurs as low as 500 m (1500 ft) in 
elevation, especially on ridges, on the higher New England 
mountains (ca. 44 degr. N) , the average transtion between broad- 
leaved hardwood forest and relatively pure forests of spruce and 
fir is at about 750 m (2500 ft) (Figure 1). Southward, the 
transition elevation increases at a rate of about 100 m per 
degree Latitude (Cogbill and White, unpublished data; Figure 1) . 
At 35 degr. N, spruce-fir is found as low as 1400 m (4500 ft), 
but a relatively pure zone of these conifers begins at 1600 to 
1700 m (5300 to 5500 ft) (Ramseur 1960, Schofield 1958, Whittaker 
1956). As noted above, these figures are dependent on 



Meon upper treelme 

SPRUCE -FIR 

Mean coniferous /deciduous 
inter toce 

• Isolated spruce -fir 

▲ Lowlond spruce - fir 

A Highest elevotion ot 

selected latitudes 



discontinuous 




43 45 47 

LATITUDE (°N) 



Figure 1. The latitude-elevation relationship for spruce- 
fir of the Appalachian mountain chain (from Cogbill and 
White, in review) . Climatic stands are those of well- 
drained mountain slopes. Edaphic stands are those of 
poorly drained lowlands. 

definition — I have used a conservative definition here and 
include only relatively pure dominance by spruce and fir on a 
variety of sites within the ecotone elevation. 

Figure 1 illustrates four important characteristics of 
southern Appalachian spruce-fir. First, there is a sizeable gap 
in the distribution of spruce-fir between about latitude 38 and 
42 degr. N, because the mountain chain does not reach high enough 
elevations within this region. Southern stands are thus quite 
isolated from northern spruce-fir. Second, the southern 
mountains are at least 100-200 m too low for a true climatic 
treeline at this latitude, thus underscoring the conclusion that 
grassy balds and heath balds (treeless southern plant 
communities) are not related to true alpine vegetation (a 
conclusion also supported on floristic grounds — see Stratton and 
White 1982, and literature cited therein). Further, the total 
available habitat for southern spruce-fir is not large. As 
narrowly defined by Saunders (1979, this volume), the original 
extent of southern Appalachian spruce-fir and spruce was probably 
only about 282 square kilometers. Figure 1 of Saunder's chapter 
in this volume shows the island-like nature of this ecosystem 
quite dramatically. In all there are only seven mountain areas 
with spruce-fir forests and an eighth with spruce forest only 
(Saunders, this volume). Finally, using the relationship 
portrayed in Figure 1 we can readily see why the areal extent of 



pre-logging spruce-fir forests in West Virginia and northern 
Virginia has been controversial (Pielka 1981; see also 
literature discussed in Pyle, this volume): the maximum 
elevations reached in that area are very close to the expected 
ecotone, 

A relict alpine flora . Despite the the lack of mountains 
high enough for a climatic treeline, six vascular plant species 
occur in the southern Appalachians which also occur at or above 
treeline in the New England mountains (Appendix I; White et al. 
1984, Ramseur I960, Bliss 1963): Agrostis borea l is, Alnus crispa, 
Arenaria groenlandica, Lycopod ium selago, Potentill a tridentata, 
and Scirpus cespitosus . To these six species can be added two 
southern Appalachian endemics which are closely related to 
northern alpine species: Juncus trif idus var. monanth es and G eum 
radiatum. Although these taxa represent a small fraction of the 
75 vascular plants restricted to the alpine zone of New England 
(Bliss 1963) , they are significant because of speculation that 
the southern mountains were cold enough for a treeline some 
12,000-20,000 yrs ago (Delcourt and Delcourt, this volume) . All 
eight species are rare and occur on rock outcrops and other high 
elevation treeless habitats. Southern Appalachian endemics also 
occur in these open habitats (e.g., Carex ruthii, Hypericum 
graveole ns , Hypericum mitchellianum, Krigia montanum f and 
Prenanthes roanensis ) ; this assemblage may represent the remnant 
of a southern Appalachian alpine meadow flora that occurred 
during the Pleistocene when a treeline was found in the southern 
mountains (White et al., 1984, Delcourt and Delcourt, this 
volume) . The importance of high elevation open habitats in GRSM 
is further underscored by the presence of two vascular plants 
which are strictly endemic to the park: Calamagrosti s cainii (a 
strict endemic of Mt. LeConte) and Glyceri a nubigena (which also 
occurs in moist shaded ground in the spruce-fir zone) (White and 
Wofford, 1984) . 

The general importance of high elevation open habitats in 
the distribution of GRSM rare plants (here defined as those 
species on state or national rare and endangered species lists) 
is depicted in Figure 2. The richness of the GRSM flora as a 
whole decreases from low to high elevations; however, when the 
richness decrease for high elevation open habitat rare species is 
normalized against this trend (as in Figure 2B) , it is seen that 
the percent of the flora which is rare increases from low to high 
elevations (see also Pittillo, this volume on the importance of 
this habitat) . 

Floristic richn ess and the islan d model. The numbers of 
vascular plants (White et al. 1984) and macrolichens (Dey this 
volume) are directly predictable from the mountaintop area of the 
southern Appalachian high peaks. Both of these studies 
investigated the hypothesis that the species-area relationship 
had the steep slope characteristic of oceanic islands (MacArthur 
and Wilson 1967) , but in both cases the slope values were 
continental in character when based on all ten of the southern 
Appalachian high peak areas. Both studies found that the data 

8 



LISTED SPECIES 

FOR = 2(%) 



2000 



£1500 



1000 



-6000 




2000 



£ EI500 



c 
o 

> 

9) 
LU 



000 



LISTED SPECIES 

% FLORA/SITE FOR = 2 



1 Uc% 


/ 


B 




^ 


J 20% J 


o - 


T 


30% 


/ / 

' 10% 


_ 


5 


6 


3 





6 


5 


1 


6 


Hydnc 


Mesic 


Submesic-subxer 


ic Xenc 



6000 



- 5000 m 

s 

< 

0) 

)00o" 



3000 



-2000 



MOISTURE GRADIENT 



MOISTURE GRADIENT 



Figure 2. Listed species of GRSM in open habitats (F0R=2) 
displayed in a 2-dimensional environmental field (from 
White 1984) . A. Richness (values in parentheses are 
the percents of all listed species restricted to open 
habitats) . B. Richness expressed as a percent of 
total expected richness at a particular environmental 
location. 



2.4 
2.3 
2.2 

O 2.0 

o 

J 1.9 
1.8 
1.7 
1.6 
1.5 



TOTAL RICHNESS 




ALL 10 
AREAS ^ 



_ 8 LARGEST 
^* AREAS 



1 1 1 I 1 I 1 1 

-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 

LOG AREA 



Figure 3. Species-area relation for vascular plants of the 
southern Appalachian high peaks (log-log formuation; 
from White et al. 1984). 



set had a stronger species-area relation if the 2 or 3 smallest 
areas were excluded. (i.e., these areas had higher richness than 
would be predicted based on their size alone) (Figure 3) . 
Interestingly, rare vascular plants (slope=.30; White and Miller, 
unpublished data) had the steep species-area relationship 
characteristic of islands. For most vascular plants, then, 
these mountaintops cannot be said to be truly insular — true 
ecological isolation is absent and the ecological contrast across 
the contour used in these studies (1680 m, 5500 ft) is probably 
low. For rarer species, however, the mountain tops may possess 
true island characteristics. Immigration and extinction rates 
were not measured by either White et al. (1984) or Dey (this 
volume) ; such measurements of the dynamics of species richness 
are needed to test the island theory directly. 

Rabenold (this volume) speculates that reduced bird richness 
in southern, compared to northern, spruce-fir may be related to 
the island-like characteristics of this habitat type in the 
south. It is, thus, likely that different biological groups as 
well as different individual species within these groups perceive 
spruce-fir differently — these may represent true insular 
situations to some groups, but not to others. 

CONSERVATION STATUS OF SOUTHERN APPALACHIAN SPRUCE-FIR 

The southern Appalachian high peaks (those that surpass 1680 
m (5500 ft)) include ten mountain areas (Table 1; see also 
Saunders, this volume). Of these, seven have well-developed 
spruce-fir forests and an eighth has well-developed spruce forest 
without fir (Saunders. Pittillo, this volume; Ramseur 1960). All 
ten areas have been at least partially disturbed by logging, 
post-logging fires, or grazing (on grassy balds that adjoin 
spruce-fir) . Logging and fire between 1880 and 1930 proved 
devastating to southern Appalachian spruce-fir (see Pyle, this 
volume, and literature cited therein) and removed about 50 
percent of the total extent of southern Appalachian spruce-fir 
ecosystem (Saunders, Pyle, this volume). Great Smoky Mountains 
National Park includes the largest remnant old growth tracts of 
this ecosystem (Pyle, Saunders, this volume) (Table 1). All of 
the areas occur within the watersheds of the Tennessee Valley 
Authority; the National Park Service (Great Smoky Mountains 
National Park, Blue Ridge Parkway), and the US Forest Service are 
important land managing agencies (Table 1) , 

The ten mountain areas are not biologically uniform 
(Pittillo, Rheinhardt, this volume) . Some of these differences 
can be attributed to differences in geology, disturbance history, 
or environment. Other differences are less easily understood and 
may be the result of more remote historic events (e.g., those of 
the Pleistocene, Delcourt and Delcourt, this volume). Local 
differences, whether of environment or history, will complicate 
the assessment of the ecosystem change across the region. 

10 



Table 1. Land ownership and presence of old growth spurce-fir 
stands on southern Appalachian high peaks. The areas are 
listed in decreasing order of size. 



Area 



Disturbance/Notes 



Land ownership' 



Great Smoky Mts. 

Balsam Mts. 

Black Mts. 

Roan Mt. 

Plott Balsams 
Craggy Mts. 

Grandfather Mt. 

Mt. Rogers 

Mt. Pisgah 

Whitetop 



Logging, fire, grazing 

Old growth stands 

Largest area of spruce-fir 

Logging, fire, grazing 



Logging, fire, grazing 
Old growth stands 

Logging, fire, grazing 



Logging, fire, grazing 



NPS-GRSM 



USFS, NPS-BRP, 
Private 

USFS, NPS-BRP, 
NC State Park 

USFS, Private, 

Nature Conservancy 

NPS-BRP, Private 



Logging, fire, grazing USFS, NPS-BRP 
Well-developed spruce-fir absent 



Logging, fire, grazing 



Logging 

Old growth stands 



Private, National 
Natural Landmark 

USFS, VA State Park 



Logging, fire, grazing USFS, NPS-BRP 
Well-developed spruce-fir absent 

Logging USFS, VA State Park 

Spruce forests present without fir 



Agency abbreviations: NPS=National Park Service, GRSM= Great 
Smosy fountains National Park, BRP=Blue Ridge Parkway, USFS=US 
Forest Service 



10a 



THE THREATS 

Despite legal protection within GRSM and several other 
conservation areas (Table 1) , the integrity of this ecosystem is 
threatened by two indirect human influences: the balsam woolly 
aphid (=adelgid, Eagar, DeSelm and Boner, this volume), an 
introduced insect pest that has been spreading in the region 
since about 1960, and atmospheric deposition of pollutants (Bogle 
and Turner, Lovett, this volume). Within the next two decades, 
remnant undisturbed southern Appalachian spruce-fir forests will 
have changed greatly in character. The changes involve several 
levels of biological organization, including physiological 
response, the loss of genotypes, local and regional extirpations 
of species, species extinction, and changes in populations, 
community structure, dynamics, and ecosystem function. The 
changes are occurring more quickly than those of post-Pleistocene 
climatic fluctuation (Delcourt and Delcourt, this volume) . To 
the immediate threats of the balsam woolly aphid and atmospheric 
deposition, we must add climatic warming due to increased carbon 
dioxide content of the atmosphere as a likely additional stress 
(Becking and Olson, 1978; Delcourt and Delcourt, this volume) . 

Whereas the balsam woolly aphid problem stimulated initial 
spruce-fir research in the mid-seventies (Eagar, this volume, and 
literature cited therein) , recent attention has shifted to the 
role of pollutant deposition in these high elevation ecosystems. 
Red spruce may be directly threatened by air pollutants: since 
1960 there has been a dramatic decline in the annual radial 
increment of red spruce in the southern Appalachains (S. 
McLaughlin, unpublished data; R. Bruck , unpublished data). 
Whether or not spruce decline can be associated with atmospheric 
deposition of pollutants and whether or not the decline is 
associated with increased spruce mortality is the subject of 
ongoing research involving the National Park Service, Oak Ridge 
National Lab, the Tennessee Valley Authority, North Carolina 
State University, and other regional institutions. Earlier work 
showed that mortality was low compared to New England (Johnson 
and Siccama 1983), but this is clearly a dynamic situation. 
Several researchers have expressed the hypothesis that 
vulnerability of Fraser fir to the balsam woolly aphid is 
effected by air pollutant stress (Eagar, this volume; R. Bruck, 
personal communication) . 

High elevation conifer ecosystems may be particularly 
vulnerable to pollutant depostion (Lovett, this volume). High 
elevation systems probably receive more deposition, as a function 
of higher precipitation and cloud immersion, than lower 
elevations. The high surface area of the needle-leaved conifers 
results in greater collection of cloud moisture. High elevation 
soils may be prone to acidification and nutrient leaching. 
Concern for high elevation ecosystems in the southern 
Appalachians is supported by reports of forest degradation in the 
northeastern United States (Siccama et al, 1982) and western 
Europe, where conifers in mountainous landscapes have also been 
involved (Plochmann 1984) . 

ll 



Although data on red spruce decline has not yet been 
published, Baes and McLaughlin (1984) have described increment 
suppression in Pinus echinata from Great Smoky Mountains National 
Park. Two periods of growth suppression were found, one between 
1863 and 1912 (during a period of smelting activity at 
Copperhill, Tennessee, 88 km upwind from the park) and the past 
20-25 years. Metal concentrations in the rings were used to 
suggest that growth suppression was caused by pollutant 
deposition. 

Pollutants in the southern Appalachians include ozone, 
nitrogen oxides, nitrate, sufate, trace elements, and acidity 
(Lovett, Bogle and Turner, this volume; Hermann and Baron 1980). 
These enter the system as gases, dryfall, wetfall, and cloud 
droplet impaction (Lovett, this volume). The interaction of the 
pollutants with vegetation and soils are not completely known at 
this time. Possible pathways include: (1) direct effects on 
leaves (e.g., ozone symptoms on sensitive species, leaching of 
nutrients from leaves, nitrogen fertilization through nitrate 
absorption in the canopy); (2) effects on soil fertility (e.g., 
through deposition of hydrogen ions leading to leaching of 
nutrient cations, through mobility of anions in soil solution 
leading to vulnerability of nutrient cations to leaching — Johnson 
and Cole 1980, Johnson and Todd 1983); (3) accumulation and 
enhanced availability of toxic elements in soils (e.g., lead, 
other trace elements, some made more available by anthropogenic 
sources of acidity, leading to toxic effects in below or above 
ground plant parts — Bogle and Turner, this volume); and (4) 
effects on root systems (e.g., aluminum or other trace element 
toxicity, leading to reduced uptake of water or nutrients, 
whether or not these are available in the soil) . All of these 
pathways may pertain in the southern Appalachians. Further, 
different pathways may be relatively more important for certain 
ecosystems or for certain species. Finally, these stresses 
interact with natural stresses like drought, as well as with the 
effects of the balsam woolly aphid. 

The complicated nature of forest decline and difficulty of 
establishing cause and effect are illustrated by the situation 
in West German forests. Five specific hypotheses have been 
advanced (adapted from Cowling 1983, C. Cronan, personal 
communication) : (1) the gaseous pollutant hypothesis (ozone and 
sulfur dioxide direct effects on above ground parts) ; (2) the 
magnesium deficiency hypothesis (deposition of acidity leaches 
calcium and magnesium from leaves and soils, enriches nitrogen 
supply via nitrate, leading to nutrient cation deficiency); (3) 
the aluminum toxicity hypothesis (increased acidity leads to 
increased concentrations of soluble aluminum, which leads to 
toxicity to fine roots) ; (4) the foliar fertilization hypothesis 
(nitrate and ammonium uptake in canopies leads to limitation of 
other nutrients and a lack of frost hardiness leadings to winter 
mortality of shoots and needles); and (5) the general stress 
hypothesis (air pollution leads to reduced photosynthesis and low 
root vigor by a variety of mechanisms, including accumulation of 

12 



trace elements and interactions with natural stresses) . A 
variety of species and forest types are affected in West Germany; 
all of the hypotheses may pertain in given situations and all of 
the factors interact with natural stresses as well. 

The acidification of soils and transmission of acidity to 
drainage waters has been a primary concern in southern 
Appalachian spruce-fir (Hermann and Baron 1980) . Spruce-fir 
soils are naturally acidic and low in buffering capacity. 
Recently, D. W. Johnson (Johnson and Cole 1980, Johnson and Todd 
1983) shifted attention from the direct effects of hydrogen ion 
deposition to the effects of anion (nitrate and sulfate) 
deposition. Since cation mobility and vulnerability to leaching 
are a function of anion mobility, Johnson hypothesized that the 
ability of a soil to immobilize anions was the key factor in 
acidification. Johnson and Todd (1983) concluded that spodosols 
under spruce-fir in the northeast had a poor sulfate absorption 
capacity (because of high organic matter content) ; this would 
presumably also apply to southern spruce-fir stands. If these 
ecosystems are near saturation for nitrate and sulfate, continued 
deposition will lead to leaching of nutrient cations and, hence, 
accelerating acidification (Johnson and Todd 1983) . This 
hypothesis forms the basis of ongoing research by D. W. Johnson 
(see below) . 

The role of organic acids in this system is poorly 
understood (Johnson and Cole 1980) . These acids may have an 
overriding influence on soil solution acidity; acidity in Raven 
Fork, Great Smoky Mountains National Park, was shown to be 
controlled by organic acids in a way a that suggested 
independence from precipitation pH (Tennessee Valley Authority, 
1983). 

There are many factors that can cause sudden losses of vigor 
and increases in tree mortality. The possibility remains that 
tree decline in southern Appalachian spruce-fir is the result of 
natural factors (an undetected pathogen, drought stress) . 

Even if air pollutants were not involved, the loss of mature 
Fraser fir trees (one of two major dominants of this forest zone) 
will bring widespread change to this ecosystem (DeSelm and Boner, 
this volume) . This loss will probably be complete in all areas 
except Mt. Rogers within the next several decades (Rheinhardt, 
Eagar, this volume). This change will effect associated species, 
including lichens of Fraser fir (Dey, this volume) , birds 
(Rabenold, this volume), and salamanders (Mathews and Echternaut, 
this volume). Our assessment of the threats to bryophytes, 
invertebrates, and mammals is hampered by lack of past population 
or community data. Changes will occur in stand microclimate 
(with increased insolation after fir death) and in ecosystem 
structure (with production of large amounts of dead organic 
matter — Nicholas and White, in press) . Lack of baseline data on 
the fungi seriously hampers efforts to predict effects on that 
group (Petersen, this volume) . The changes may also influence 
soil solution chemistry and, thus, potentially effect stream 

13 



communities as well. Indirect effects to understory plants will 
occur as a result of increased shrub cover and release of 
understory saplings (DeSelm and Boner, this volume). The 
response of organisms and soils to air pollutants will also be 
affected by the concurrent loss of Fraser fir. 

The possibility of aphid resistant Abies genotypes on Mt. 
Rogers is of particular interest (Rheinhardt, Eagar, this 
volume) . There is also a possibility for longterm Fraser fir 
persistence elsewhere in the southern Appalachians. Since aphid 
infestations on seedlings and saplings are possibly maintained by 
spread from mature trees (Eagar, this volume) and since mortality 
of younger trees is less pronounced, the possibility remains 
that a shifting steady state of infested and uninfested patches 
will occur, with the aphid becoming locally extinct as mature 
trees are lost, thus giving an opportunity for stand 
regeneration. It is not now known whether a long term 
equilibrium of such patches will occur; further, it will be of 
crucial importance to find out if the cycle between patches is 
long enough for successful seed crop production of Fraser fir. 
This does suggest an important research direction in terms of 
projecting the future state of this system: local persistence of 
aphids after death of mature trees, spread rates from isolated 
infestations, and growth rates of fir saplings would all have to 
be quantified and modelled. The conservation importance of such 
an effort is clear: that research will define the extinction 
probability of Fraser fir as a species over the next two to five 
decades. 

The structure and dynamics of undisturbed spruce-fir forest 
changes with elevation, slope aspect, and slope position 
(Whittaker 1956, Crandall 1958). Growth rates and maximum tree 
sizes tend to decrease with elevation and from moist (coves) to 
dry (ridge) sites. Within one site type and elevation, treefall 
gaps cause more local variations in density and basal area (White 
et al., in press); the frequency of v/indthrow probably increases 
from sheltered to exposed locations. Disturbance history is also 
a controlling influence on stand structure and growth. As a 
result, the phrasing of hypotheses and the organization of 
sampling stratification will be crucial factors in the assessment 
of the impact of threats to the spruce-fir ecosystem. 
Investigators must control for the other influences on stand 
structure and growth in order to examine the independent effects 
of the loss of fir and deposition of pollutants. 

ECOSYSTEM STUDIES: 
BIOMASS, PRODUCTIVITY, AND NUTRIENT CYCLING 

The spread of air pollutants to the southern Appalachians 
underscores the importance of ecosystem level research. Example 
of key research areas include the influence of pollutant 
chemistry on nutrient cycling and the importance of decomposers 
in the fate of large amounts of organic debris. Therefore, I 
will briefly review past work on ecosystem structure and function 
in southern Appalachian spruce-fir. 

14 



Standing crop biomass and net annual production was been 
assessed in the Great Smoky Mountains by R. H. Whittaker in a 
series of papers (Whittaker 1961, 1962, 1963, 1965, 1966; 
Whittaker and Garfine 1962). Whittaker's initial papers assessed 
sampling technique for annual production. Shrub species and 
heath balds were the focus of much of this work. The most 
important summary is presented by Whittaker (1966) , in which five 
of the samples were spruce-fir or fir stands. Spruce-fir forests 
were shown to have lower biomass than low elevations forests, but 
higher biomass than old growth hardwood forests at comparable 
elevations. Spruce-fir had relatively high biomass accumulation 
ratios (total biomass/net annual above ground production) , low 
ratios of annual net production to leaf weight or leaf area, and 
high leaf areas. Although Whittaker' s data are important for 
comparative purposes, he did not publish allometric equations for 
the estimation of biomass from measurement of stand basal area. 

Shanks and Olson (1961) investigated the decomposition of 
leaves in a series of stands. They demonstrated the 
comparatively slow decomposition of organic matter in spruce-fir 
stands. Shanks and Clebsch (1962) used allometric equations to 
estimate the standing crop biomass and elemental composition in 
red spruce. Other data collected in the 1960s (Shanks et al. 
1961) described the standing crop biomass, and elemental 
concentrations and pools of a variety of woody and herbaceous 
plants. Standing crop biomass, elemental concentration, and 
total element content was also described for annual litter fall. 

Wolfe (1967) analyzed spruce-fir soils and reported the 
influence of vegetation, tree throws, and bedrock on soil 
morphology and nutrient content. Profile charts were presented 
showing elemental compostion with soil depth. 

Weaver (1972; Weaver and DeSelm, 1973) studied a series of 
stands in the Balsam Mountains, some of which occur within the 
Blue Ridge Parkway corridor. These stands included young (40-50 
yr old) spruce-fir, young yellow birch, and mature (>100 yr old) 
yellow birch. Although Weaver studied a narrow range of stand 
types and elevations, his data include the best allometric 
equations for the estimation of biomass in southern spruce-fir. 
Annual production, net assimilation rates, deposition chemistry 
and rates, nutrient pools, and cycling rates were discussed. 

These studies found that biomass was heavily concentrated in 
the tree stratum and varied from 100 metric tons/ha (in young 
spruce-fir stands, Weaver 1972) to 340 metric tons/ha (in old 
growth spruce-fir stands, Whittaker 1966). Summit type pure 
Fraser fir stands had 200 metric tons/ha (Whittaker 1966) . Net 
annual production varied from about 600 to 1500 grams/square 
meter/yr (Shanks et al. 1961, Weaver 1972). Important nutrient 
pools were living biomass and organic matter in the soil. 
Transfer of nutrients out of these pools was found to be a slow 
process (Shanks and Olson 1961, Shanks et al. 1961). The ratio 
of biomass to annual productivity is high; thus, the rate of 

15 



nutrient availability is limited under normal conditions (Shanks 
and Olson 1961) . Heavy tree mortality may result in pulses of 
nutrient availability. Because of slow growth rates, the 
vegetaton may not be able to immobilize these nutrients in 
biomass, resulting in vulnerability to degradation in site 
fertility. 

ONGOING RESEARCH IN GRSM 

The ongoing research concerning GRSM spruce-fir and 
pollutant deposition was recently summarized by Eagar et al. 
(1984) . The projects include research on the physiological 
(e.g., pollutant effects), population (mortality, regeneration), 
community (structure, dynamics) , and ecosystem (organic matter 
decomposition, pollutant movements), levels; in addition, there 
is research characterizing soils, environment, and pollutant 
loading (Table 2) . 

This research effort is a recent and developing one. Thus, 
some research areas are not yet included in the scope of the 
ongoing studies. For example, the following projects are 
important additional studies: (1) analysis of historic droughts 
(which may interact with pollutant stress) , (2) more detailed 
work on plant pathology, (3) population or community level work 
on additional taxonomic groups (snails, soil macroinvertebrates, 
salamanders, mosses), (4) tree root studies (e.g., field surveys 
of vigor and experimental studies of pollutant effects) , (5) 
expansion of modelling (including a Fraser fir patch dynamics 
model, to address the extinction risk for this species), and (6) 
expansion of ecosystem process studies (including linkages 
between terrestrial and aquatic systems) . Most of the ecosystem 
level work concerns specific hypotheses and intensive study 
sites; a project to characterize ecosystem function on a broader 
scale is needed. Finally, identification of the causes of 
ecosystem change will likely require field experiments, in 
addition to the laboratory experiments now planned. 

We have presented a bibliography of southern Appalachian 
spruce-fir research in Appendix II to this document. Uplands 
Field Research Lab is also publishes a bibliographic series on 
the human and natural history of the southern Appalachians. 
Although these contain references on all regional ecosystems, 
they are indexed to specific ecosystem types, including spruce- 
fir. Reports that have been prepared to date include the 
following subjects: vegetation (DeYoung et al., 1982), 
phanerogam systematics (Wofford and White 1981) , pteridophyte 
systematics and ecology (Evans et al. 1981), lichen systematics 
and ecology (DePriest 1984) , geology and geomorphology (Yurkovich 
1984), soils (Springer et al., in press), and lichen systematics 
and ecology (DePriest, in press). 



16 



Table 2. Ongoing research projects in Great Smoky Mountains 
National Park on spruce-fir and pollutant deposition. 



Research category/project 



Institution Year 



Physiological level 

Tree ring and trace element analysis ORNL 

Tree vigor/condition NPS 

Tree vigor/condition NCSU 

Rare plant sensitivity to pollutants NCSU 

Red spruce sensitivity to pollutants NCSU 

Population level 

Rare plant population monitoring plots NPS 

Small mammal survey UT 

Community level 

Permanent vegetation plots (incl. tree NPS 

mortality, regeneration, community 

composition and structure, all strata) 

Disturbance history and mapping NPS 

Vegetation mapping/remote sensing NPS 

Vegetation mapping/aerial photography NPS 
History/chronosequence of fir and spruce USFS 

mortality using aerial photography 
Forest fuel loadings as affected by 

balsam woolly aphid NPS 

Gap dynamics/modelling UT 

Ecosystem level 

Organic matter decomposition NPS 
Pollutant deposition and interactions 

with canopy and soils ORNL 

TVA Raven Fork study TVA 

Soil characterizations 

Soils map SCS 

Soil samples on vegetation plots NPS 

Soil samples on vegetation plots NCSU 

Pollutant loading/monitoring 

Elemental analysis of herbs, tree foliage, 

litter, and soils ORNL 

Fog interception/throughfall processes ORNL 

Sulfur accumulation in lichens NPS 



1983-85 

1984-85 

1984 

1983-85 

1984-85 



1981-83 
1984-86 



1984-85 



1983-85 
1982-85 
1982 
1984-85 



1983 
1983 



1984-85 

1984-88 
1981-84 



1984-85 
1984-85 
1984 



1984 

1984-88 

1983-84 



Meteorological/atmospheric deposition 



NPS, TVA, TN 1981-90 



Institutional abbreviations: NPS=National Park Service, 
ORNL=Oak Ridge National Lab, UT=University of Tennessee, NCSU- 
North Carolina State, TVA=Tennessee Valley Authority, 
TN=state of Tennessee, SCS=Soil Conservation Service, USFS=US 
Forest Service. 



16a 



CONCLUSIONS 

Southern Appalachian spruce-fir is a unique, island-like and 
geographically restricted ecosystem type. The last undisturbed 
stands of this ecosystem are now threatened. These stands are a 
remnant of the pre-logging distribution of this type. Even pre- 
logging spruce-fir had been in a state of flux, however (see 
Delcourt and Delcourt, this volume). Natural changes in climate 
and distribution probably allowed local evolution of gene pools 
on the isolated, island-like, spruce-fir areas. More recent, 
human-caused, changes are occurring more quickly than those of 
the post-Pleistocene: Abies f raseri , a forest dominant, 
populations will have become drastically altered within the 
relatively short period between 1960 and 2000. During this 
period of change, there is an opportunity for the study of an 
ecosystem under stress and to evaluate changes in natural 
ecosystem processes and the risk of species loss. The nature of 
the threats changes underscores the importance of ecological and 
whole system research. The pervading influence of pollutants 
mandates research on an ecosystem process level. Because the 
structure, composition, and function of this ecosystem vary with 
site factors (elevation, slope aspect, slope shape), geography, 
and disturbance history, studies on ecosystem change will 
require careful phrasing of hypotheses. The research is likely 
to be long term. Whether the stability of this ecosystem can be 
promoted and whether its component species can be better 
protected is a matter of research and policy debate. On the one 
hand, the southern Appalachian spruce-fir ecosystem represents a 
bell-weather of change in man's environment and can be studied on 
that level alone. On the other hand, protection of stands or 
individual species may in some cases be both desirable and 
feasible and may require active management. 

LITERATURE CITED 

Baes, C. F., Ill, and S. B. McLaughlin. In press. Trace 
elements in tree rings: evidence of recent and historical 
air pollution. Science. 

Becking, R. W., and J. S. Olson. 1978. Remeasurement of 
permanent vegetation plots in the Great Smoky Mountains 
National Park, Tennessee, USA, and the implications of 
climatic changes on vegetation. Oak Ridge National 
Laboratory, Environmental Science Division, Publ. No. 1111. 
94 p. 

Bliss, L. C. 1963. Alpine plant communities of the Presidential 
Range, New Hampshire. Ecol. 44:678-697. 

Cogbill, C. V., and P. S. White. In review. Montane spruce-fir 
forest and treeline along the Appalachian Mountain chain. 

Cowling, E. B. 1983. Observations in German forests during the 
late summer of 1983. Typescript. North Carolina State 

17 



University, Raleigh. 

Crandall, D. L. 1958. Ground vegetation patterns of the spruce- 
fir area of the Great Smoky Mountains National Park. Ecol. 
Monogr. 28:337-360. 

DePriest, P. In pres"s. Lichens of the southern Appalachians, 
an indexed bibliography. National Park Service, Southeast 
Regional Office, Res. /Resource Manage. Rept. 

DeYoung, H. R., P. S. White, and H. R. DeSelm. 1982. Vegetation 
of the southern Appalachians: an indexed bibliography, 
1805-1982. National Park Service, Southeast Regional 
Office, Res. /Resource Manage. Rept. SER-63. 94 p. 

Eagar, C, P. S. White, and D. Silsbee. 1984. Monitoring and 
research related to atmospheric deposition in Great Smoky 
Mountains National Park, North Carolina and Tennessee. 
Proc. National Acid Precipitation Assessment Program, 
Aquatics effects task group and terrestrial effects task 
group, Peer Review Meeting, November, 1984, Ashville, NC. 

Evans, M., P. S. White, and C. Pyle. 1981. Southern Appalachian 
pteridophytes: an indexed bibliography, 1833-1980. 
National Park Service, Southeast Regional Office, 
Res. /Resource Manage. Rept. 44. 35 p. 

Fahey, T. J., and W. A. Reiners. 1981. Fire in the forests of 
Maine and New Hampshire. Bull. Torr. Bot. Club 108:362-373. 

Foster, J. R., and W. A. Reiners. 1983. Vegetation patterns in 
a virgin subalpine forest at Crawford Notch, White 
Mountains, New Hampshire. Bull, Torr. Bot. Club 110:141- 
153. 

Harmon, M. E. 1981. Fire history of Great Smoky Mountains 
National Park, 1940-1979. National Park Service, Southeast 
Regional Office, Res. /Resource Management Rept. 46. 39 p. 

Harmon, M. E., S. P. Bratton, and P. S. White. 1984. 

Disturbance and vegetation response in relation to 

environmental gradients in the Great Smoky Mountains. 
Vegetatio 55:129-139* 

Heinselman, M. L. 1981. Fire and succession in the conifer 
forests of northern America. Pages 374-405 in D. C. West, 
H. H. Shugart, and D. B. Botkin (eds.), Forest succession. 
Springer-Verlag . New York. 

Hermann, R., and J. Baron. 1980. Aluminum mobilization in acid 
stream environments, Great Smoky Mountains National Park, 
USA. Proc. Int. Conf. Ecol. Impact Acid Precip. Norway: 
218-219. 

Holt, P. C. (ed.) 1970. The distributional history of the biota 

18 



of the southern Appalachians. Part II. Flora. Virginia 
Polytechnic Institute and State University, Elacksburg. 
Research Division Monograph 2. 

Johnson, A. H. f and T. G. Siccama. 1983. Acid deposition and 
forest decline. Environ. Sci. & Tech. 17:294A-305A. 

Johnson, D. W., and D. W. Cole. 1980. Anion mobility in soils: 
relevance to nutrient transport from forest ecosystems. 
Environ. Internat. 3:79-90. 

Johnson, D. W., and D. E. Todd. 1983. Relationships among iron, 
aluminium, carbon, and sulfate in a variety of forest soils. 
Soil Sci. Soc. Amer. J. 47:792-800. 

LaRoi, G. H. 1967. Ecological studies in the boreal spruce-fir 
forests of the North American taiga. Ecol. Monogr. 37:229- 
253. 

Larsen, J. A. 1980. The boreal ecosystem. Academic Press. New 
York. 500 p. 

MacArthur, R. H., and E. 0. Wilson. 1967. The theory of island 
biogeography. Princeton Univ. Press, Princeton, NJ. 203 p. 

Nicholas, N. S., and P. S. White. In press. The effect of 
balsam woolly aphid infestation on fuel loading in spruce- 
fir forests of Great Smoky Mountains National Park. 
National Park Service, Southeast Regional Office, 
Res ./Resource Manage. Rept. 

Oosting, H. J., and D. W. Billings. 1951. A comparison of 
virgin spruce-fir forest in the northern and southern 
Appalachian system. Ecol. 32:84-103. 

Pielke, R. A. 1981. The distribution of spruce in west-central 
Virginia, before logging. Castanea 46:201-216. 

Plochmann, R. 1984. Air pollution and the dying forests of 
Europe. Amer. For., June, 1984, pp 17-21, 56. 

Ramseur, G. S. 1960. The vascular flora of the high mountain 
communities of the southern Appalachians. J. Elisha 
Mitchell Sci. Soc. 76:82-112. 

Reiners, W. A., and G. E. Lang. 1979. Vegetational patterns and 
processes in the balsam fir zone, White Mountains, New 
Hampshire. Ecol. 60:403-417. 

Saunders, P. R. 1979. Vegetational impact of human disturbance 
on the spruce-fir of the southern Appalachian mountains. 
Ph. D. Dissertation, Duke Univ., Durham, NC. 177 p. 

Schofield, W. B. 1960. The ecotone between spruce-fir and 
deciduous forest in the Great Smoky Mountains. Ph.D. 

19 



Dissertation, Duke Univ., Durham, NC. 176 p. 

Shanks, R. E. 1954. Climates of the Great Smoky Mountains. 
Ecol. 35:354-361. 

Shanks, R. E., and E. E. C. Clebsch. 1962. Computer programs 
for the estimation of forest stand weight and mineral pool. 
Ecol. 43:339-341. 

Shanks, R. E., E. E. C. Clebsch, and H. R. DeSelm. 1961. 

Estimation of standing crop and cycling rate of minerals in 

Appalachian ecosystems. Unpublished ms . , University of 
Tennessee. Knoxville. 14 p. 

Shanks, R. E., and J. S. Olson. 1961. First-year breakdown of 
litter in southern Appalachian forests. Science 134:194- 
195. 

Siccama, T. G. 1974. Vegetation, soil, and climate on the Green 
Mountains of Vermont. Ecol. Monogr. 44:325-349. 

Siccama, T. G., M. Bliss, and H. W. Vogelmann. 1982. Decline of 
red spruce in the Green Mountains of Vermont. Bull. Torr. 
Bot. Club 109:162-168. 

Springer, M. E., P. S. White, and D. Holland. In press. Soils 
of the southern Appalachians, an indexed bibliography. 
National Park Service, Southeast Regional Office, 
Res. /Resource Manage. Rept. 

Sprugel, D. G. 1976. Dynamic structure of wave-regenerated 
Abies bals amea forests in the northeastern United States. 
J. Ecol. 64:889-911. 

Stratton, D. A., and P. S. White. 1982. Grassy balds of Great 
Smoky Mountains National Park: vascular plant floristics, 
rare plant distribution, and an assessment of the floristic 
data base. National Park Service, Southeast Regional 
Office, Res. /Resource Management Rept. SER-58. 33 p. 

Tennessee Valley Authority. 1983. Investigation of the cause of 
fish kills in fish rearing facilities in Raven Fork 
watershed. Division of Air and Water Resources, Tennessee 
Valley Authority, Knoxville, Tenn. 60 p + 10 Appendices. 

Weaver, G. T. 1972. Dry matter production and nutrient dynamics 
in red spruce-Fraser fir and yellow birch ecosystems in the 
Balsam Mountains, western North Carolina. Ph.D. 
Dissertation, University of Tennessee, Knoxville. 406 p. 

Weaver, G. T., and H. R. DeSelm. 1973. Biomass distribution 
patterns in adjacent coniferous and deciduous forest 
ecosystems. IUFRO Biomass Studies S4. 01:413-427. 

White, P. S. 1976. The upland forest vegetation of the Second 

20 



College Grant, New Hampshire. Ph. D. Dissertation, 
Dartmouth College, Hanover, NH. 294 p. 

White, P. S. 1984. Impacts of cultural and historic resources 
on natural diversity: lessons from Great Smoky Mountains 
National Park, North Carolina and Tennessee. Pages 119-132 
in J. L. Cooley and J. H. Cooley (eds.), Natural diversity 
in forested ecosystems. Institute of Ecology, University of 
Georgia. Athens. 

White, P. S., M. D. MacKenzie, and R. T. Busing. In press. 
Natural disturbance and gap phase dynamics in southern 
Appalachian spruce-fir forests, USA. Can. J. For. Res. 

White, P. S., R. I. Miller, and G. S. Ramseur. 1984. The 
species-area relationship of the southern Appalachian high 
peaks: vascular plant richness and rare plant 
distributions. Castanea 49:47-61. 

White, P. S., and B. E. Wofford. 1984. Rare native vascular 
plants in the flora of Great Smoky Mountains National Park. 
J. Tenn. Acad. Sci. 59:61-64. 

Whittaker, R. H. 1956. The vegetation of the Great Smoky 
Mountains. Ecol. Monogr. 26:1-80. 

Whittaker, R. H. 1961. Estimation of net primary production of 
forest and shrub communities. Ecol. 42:177-180. 

Whittaker, R. H. 1962. Net production relations of shrubs in 
the Great Smoky Mountains. Ecol. 43:357-377. 

Whittaker, R. H. 1963. Net production of heath balds and forest 
shrubs in the Great Smoky Mountains. Ecol. 44:176-182. 

Whittaker, R. H. 1965. Branch dimensions and estimation of 
branch production. Ecol. 46:365-370. 

Whittaker, R. H. 1966. Forest dimensions and production in the 
Great Smoky Mountains. Ecol. 47:103-121. 

Whittaker, R. H. and V. Garfine. 1962. Leaf characteristics 
and chlorophyll in relation to exposure and production in 
Rhododendr on maximum . Ecol. 43:120-125. 

Wofford, B. E., and P. S. White. 1981. Systematics and 
identification of southern Appalachian phanerogams: an 
indexed bibliography. National Park Service, Southeast 
Regional Office, Res. /Resource Manage. Rept. SER-53. 69 p. 

Yurkovich, S. P. 1984. Geology and geomorphology of the 
southern central Blue Ridge: an indexed bibliography. 
National Park Service, Southeast Regional Office, 
Res. /Resource Manage. Rept. 67. 75 p. 

21 



LATE -QUATERNARY HISTORY OF THE SPRUCE-FIR ECOSYSTEM 
IN THE SOUTHERN APPALACHIAN MOUNTAIN REGION 

1/ 9/ 

Hazel R. Delcourt— and Paul A. Delcourt—' 

Abstract . --We have prepared contoured maps of dominance for 
spruce (Picea) and fir ( Abies ) for selected times between 18,000 
YR BP (Years Before Present) and YR BP. These maps are based 
on calibrated fossil pollen data derived from thirteen radio- 
carbon-dated late -Quaternary sites located south of the glacial 
margin in eastern North America. During the full- and late- 
glacial interval, from 18,000 YR BP to 12,500 YR BP, spruce-fir 
forests were distributed across a broad latitudinal belt, 
extending eastward from Missouri across Tennessee and into the 
Carolinas. With major climatic amelioration after 12,500 YR BP, 
populations of both spruce and fir were progressively restricted 
in distribution to the Southern Appalachian Region, first to the 
area from the Cumberland and Allegheny Plateaus across to the 
Piedmont, and then to higher elevations in the Blue Ridge 
Province, such as in the Great Smoky Mountains. During the 
period of peak warmth and aridity in the mid-Holocene, from 
about 8,000 YR BP to 4,000 YR BP, spruce and fir populations 
were isolated at high elevations in the southern Appalachians 
and were separated from their main population centers in the 
northern Appalachians, New England, and Canada. During the past 
4,000 years, climatic cooling has resulted in reexpansion of 
boreal species populations southward and to lower elevations in 
the Appalachian Mountains. The areal extent of boreal forests 
in the southeastern United States has changed greatly in the past 
18,000 years, from a full-glacial maximum of 1,800,000 knr to a 
mid-Holocene minimum of about 100 km2. The future trend would 
be toward expansion in area, unless the populations of the dom- 
inant arboreal species are eliminated by uncontrolled pathogens 
or by anthropogenic factors such as C02-induced climatic change. 

Additional keywords : Abies fraseri , paleoecology of boreal 
forests, Picea rubens , pollen-vegetation calibrations, tree 
migrations. 



1/ 
Research Assistant Professor, Department of Botany and Graduate Program 
in Ecology, University of Tennessee, Knoxville, Tenn. 

2/ 

Assistant Professor, Department of Geological Sciences and Graduate 
Program in Ecology, University of Tennessee, Knoxville, Tenn. 

This research was sponsored by grants DEB-80-04168 and BSR-83-00345 from 
the Ecology Program of the National Science Foundation to the University 
of Tennessee. Contribution Number 29, Program for Quaternary Studies of 
the Southeastern United States, University of Tennessee, Knoxville. 



22 



INTRODUCTION 

Forests dominated by red spruce ( Picea rubens Sarg.) and Fraser fir 
( Abies fraseri (Pursh.) Poir.) occupy approximately 120 km2 in the 
southern Appalachian Mountains of southwestern Virginia, western North 
Carolina, and East Tennessee (Ramseur 1960; White this volume ). Spruce 
and fir forests of the southern Appalachian region are generally confined 
to ten mountain peaks above an elevation of 1675 m, with the largest 
contiguous area of spruce- fir forest located in the Great Smoky Mountains 
National Park of Tennessee-North Carolina (Ramseur 1960; White this 
volume ). These "islands" of spruce-fir forest are the object of intensive 
study because of the recent introduction and outbreak of an insect 
pathogen , the balsam wooly aphid that today threaten to eliminate their 
host tree species from the southern Appalachian region. 



In the Great Smoky Mountains, the spruce- fir ecosystem traditionally 
has been viewed as the high-elevation endpoint in vegetation along an 
environmental gradient from warm- temperate to boreal communities 
(Whittaker 1956). Although the structure, composition, and climatic 
requirements of spruce- fir forests of the Gr?at Smoky Mountains have been 
compared with those of red spruce-balsam fir ( Abies balsamea (L.) Mill.) 
forests at low elevations farther north in Maine and New Brunswick (Shanks 
1954), relatively little research has been attempted to determine the 
historical relationships of these forest communities through paleo- 
ecological studies of late -Quaternary changes in their distribution, areal 
coverage, and composition. Yet, such studies are vital as a perspective 
for understanding the development of the present-day communities as well 
as determining the potential for their resilience following anthropogenic 
disturbance. 

In this paper, we review the Quaternary history of spruce-fir forests 
as currently known for the region south of the glacial margin in eastern 
North America. Using calibrations of percent dominance (growing stock 
volume) versus percent arboreal pollen based upon extensive compilations 
of fore st- inventory and surface pollen-sample data, we present a series of 
mans that depict changes in dominance of spruce and fir over the past 18,000 
years in the southeastern United States. These maps indicate changing 
patterns in population centers as well as range margins. They make 
possible, for the first time, analysis of the degree to which the changes 
in distribution of these two taxa have coincided and the extent to which 
their migrations have been individualistic. Maps based upon fossil pollen 
sites spaced widely across the region offer a broad-scale perspective of 
vegetational change (Davis 1981; Delcourt and Delcourt 1981). Future 
refinements in paleoecological research will allow examination of climatic 
and geomorphic processes as elements of changing disturbance regimes 
affecting plant community composition in the southern Appalachians on time 
scales of hundreds to thousands of years. 



23 



REGIONAL VEGETATION HISTORY 

Abies has been an element of the flora of the southeastern United 
States since the Eocene Epoch of the Tertiary Period, with Picea first 
recorded in the paleobotanical record in the Miocene Epoch (Graham 1973). 
Although both genera have persisted in the Southeast since the Tertiary, 
only in the past 1 to 2 million years of the Quaternary Period have they 
become regionally dominant in the vegetation. Their areal dominance has 
fluctuated during approximately 20 glacial/interglacial climatic cycles 
(Ruddiman and Mclntyre 1976). During about 907=, of the past 1 million 
years, climatic conditions were colder than today (Emiliani 1972) and 
were favorable for widespread occurrence of boreal forests in mid- 
latitudes of the Southeast (north of 34° N latitude). 

The vegetation patterns of the last (Wisconsinan) glacial maximum can 
be considered representative of the majority of the Pleistocene Epoch. 
Between 23,000 YR BP and 18,000 YR BP, boreal forests dominated by spruce, 
jack pine (Pinus banks iana Lamb.), fir, and tamarack (Larix laricina (Du 
Roi) K. Koch) covered an area of 1,800,000 km across a broad latitudinal 
belt between the Ohio and Upper Mississippi river valleys and northern 
Louisiana, Mississippi, Alabama, Georgia, and South Carolina (Delcourt 
and Delcourt 1979, 1981; Watts 1980a). Warm- temperate forests occurred 
south of about 34° N latitude during full-glacial times. Deglaciation of 
the area in eastern North America covered by the Laurentide Ice Sheet began 
by 17,000 YR BP (Dreimanis 1977). This climatic amelioration resulted 
in vegetational response at 34° to 36° N latitude. In Tennessee and the 
Carolinas, dominance of jack pine began to diminish by 16,500 YR BP. 
Northern pines were replaced by hardwoods, with an increase in both spruce 
and fir. These vegetational changes reflected increased moisture and also 
decreased seasonal extremes in temperature, with increasing predominance 
of the Maritime Tropical Airmass originating in the Gulf of Mexico (Delcourt 
and Delcourt 1983). Boreal forests were largely replaced by temperate 
forests at 36° N latitude by 12,500 YR BP, with jack pine, fir, and spruce 
migrating rapidly northward on their leading front (Davis 1981). 
Populations of these boreal taxa declined rapidly at their southern limits 
of distribution (Bernabo and Webb 1977). During the past 10,000 years 
of the Holocene Epoch, boreal forests have been restricted to latitudes 
north of 45° N and to elevations in the central and southern Appalachians 
generally above 1500 m. 

METHODS AND RESULTS 

We used the Quaternary pollen records available from thirteen 
radiocarbon-dated sites in the region south of the glacial margin in 
eastern North America (fig. 1) to examine broad-scale changes in distribu- 
tion and dominance of spruce and fir over the past 18,000 years (Barclay 
1957; Craig 1969; Watts 1970, 1979, 1980b; King 1973; Delcourt 1979, 1980; 
Watts and Stuiver 1980; Delcourt et al. 1980, 1983; Kolb and Fredlund 1981; 
Whitehead 1981). At each of the tKirteen fossil-pollen sites, we converted 
values for percent arboreal pollen (AP) to percent of forest vegetation 
for selected times from 18,000 YR BP to the present. We used calibrations 
derived from an array of 1742 county and forest inventory-unit summaries 



24 



3S/G 




done r SPRINGS 



CRANBERRY GLAOES; 

• /"• 'TV' 

HACK POND 



SHADY VALLEY ».. 

i&"-V ' ' ROCKYHOCK} 

•ANDERSON POND BAY , 



NONCONNAM CREEK 



WHITE PQNO 



" RAYBURN 
• SALT. DOME | 



. -. QUICKSAND 

CAHA*BA \ P0N0 ■ 
• POND '• 



JtOSHEN 
*SP/»NGS 




TULL- 
GLACIAL 

'•'l1!kY r shore 




Figure 1. — Location map of late-Quaternary fossil-pollen sites. 

and 1684 modern pollen samples distributed between 25° and 60° N latitude 
and 50° to 105° W longitude (Delcourt et al. in press ). We used geometric- 
mean linear regression to establish the modern relationship of percent 
pollen to percent growing-stock volume for both Picea (table 1, fig. 2) 
and Abies (table 1, fig. 3). 

Table 1. --Results of geometric -mean linear regression of percent arboreal 
pollen versus percent growing- stock volume for Picea and Abies 
in eastern North America. Asterisks (**) indicate highly 
significant values at the 0.01 level. 



Taxon 



Picea 



Abies 



Slope (r) 
Y-intercept (p ) 
Pearson product-moment 

correlation coefficient 
Number of data pairs 



1.10** 
.5.28** 

0.80** 
601 



0.44** 
■2.35** 

0.30** 
491 



LIBRARY 

25 GREAT SMOKY 

NATIONAL PAHK 



PtCCA 



rtu> 
too 



ro 



40 



M 



.* ♦ 



*i\ * * 



♦ » 






M 

rem* 



»♦ 

t 



Figure 2. — Scatter plot of percent arboreal pollen (PCTPOL) versus percent 
growing-stock volume (PCTGSV) for Picea in eastern North America. 

The slope and intercept parameters derived from these regressions and 
those of 18 additional tree taxa were used to recalculate percent dominance 
of Picea and Abies within the forests at each fossil locality, by the 
following equations (Prentice 1982): 



Pa" p o 



where p £ p 
r a o 



(1) 



where v is a preliminary paleovegetation value, 

p is the pollen percentage based on the sum of the arboreal pollen, 

p is the y-intercept of the regression, and 
o 

r is the slope of the regression. 

If p a = 0, then v a = (2) 

The resulting v values were corrected, based upon the sum of v a 
values for all 20 calibrated taxa at a site for a specific time, in order 
to represent a paleovegetation value (v ) for each taxon based upon 1007, 
recalculated vegetation: 



26 



AOItS 



rt 



to 



• ♦ 






* ♦! » • 



10 



N 



30 



•0 



ro 



PCTCS* 



Figure 3. — Scatter plot of percent arboreal pollen (PCTPOL) versus percent 
growing-stock volume (PCTGSV) for Abies in eastern North America, 



v = X 100 

c 



E*. 



(3) 



We plotted values for recalculated paleovegetation (v ) for Picea and 
Abies for each site on maps (figs. 4, S) depicting full-gl£cial (18,000 
YR BP), late-glacial (14,000 YR BP), early Holocene (10,000 YR BP) , mid- 
Holocene (6,000 YR BP), late Holocene (2,000 YR BP), and post-EuroAmerican 
settlement (0 YR BP). On each map (figs. 4, 5), solid dots designate sites 
with pollen data at the specified time. Open dots indicate locations of 
additional sites that were used in the study but did not have information 
for the time indicated on the map. For each time represented, contours were 
drawn at 10% intervals where dominance values range to 607. or greater. 
Contours were added at 57. intervals on maps with values of dominance 
ranging up to 257*. Mapped positions of the marine shoreline, margin of the 
Laurentide Ice Sheet, proglaclal lakes, and postglacial lakes follows 
Delcourt and Delcourt (1981). 



27 





PICEA 
% OF VEGETATION 





PICEA 
% OF VEGETATION 



LAURENTIDE ICE SHEET 




60 




A 



PICEA 
% OF VEGETATION 



LAURENTOE CE SHEET 




%0F VEGETATION 



Figure 4. --Dominance maps for Picea in the southeastern United States, 



28 




ABIES 
% OF VEGETATION 



Figure 5 . —Dominance maps for Abies in Che southeastern United States, 



29 



DISCUSSION 

Full-glacial (18,000 YR BP) 

During the height of the late Wisconsinan full-glacial period, 
represented by the map for 18,000 YR BP (fig. 4), the distribution of 
spruce was concentrated in a broad latitudinal belt extending eastward 
from Missouri across Tennessee and into the Carolinas. Zero values to the 
north in the Allegheny Mountains of West Virginia and Pennsylvania mark 
the full-glacial ecotone between boreal forest and tundra (Watts 1979). 
This boundary is not known with certainty to the west of the Appalachian 
Mountains, but a narrow zone of tundra probably bordered the Laurent ide Ice 
Sheet along its southern margin (Delcourt and Delcourt 1981). Alpine 
tundra may also have existed on mountain peaks above 1500 m in the southern 
Blue Ridge Province, but this speculation (Delcourt and Delcourt 1981) has 
yet to be tested with appropriate paleoecological sites. 

Two full-glacial population centers are evident for Picea (fig. 4). 
Spruce constituted over 607, of the forests from West Tennessee across 
Missouri, and spruce also reached up to 407, in the central Appalachian 
Mountains. Spruce percentages were low in the Interior Low Plateau of 
Tennessee, where jack pine was dominant in the full-glacial (Delcourt 1979), 
Eastern populations were probably those of black spruce ( Picea mariana 
(Mill.) B.S.P.) and red spruce ( Picea ' rubens Sarg.) (Watts 1979), whereas 
western populations were probably mostly white spruce ( Picea glauca 
(Moench) Voss) (Delcourt and Delcourt 1977; Delcourt ejt al . 1980). As in 
the modern boreal forests of eastern Canada (Delcourt ejt al. in press ), 
in the full-glacial spruce was dominant at its northern limit of distribu- 
tion, and its dominance diminished more gradually toward its southern 
boundary. As today, the southern limit of spruce 18,000 YR BP coincided 
with the ecotone between boreal coniferous and cool- temperate deciduous 
forests. 

The distribution of Abies during the full-glacial was even more 
strongly confined to a narrow east-west belt, constituting up to 107, of the 
forests in Tennessee and North Carolina at 36° to 37° N latitude (fig. 5). 
Dominance of fir diminished to zero northward in Virginia and southward in 
Georgia and South Carolina (fig. 5). Today, balsam fir ( Abies balsamea 
(L.) Mill.) is 107 o or more of the growing-stock volume from eastern Ontario 
to the maritime provinces of eastern Canada (Delcourt e_t al. in press ). 

The concentration of both spruce and fir north of 34° N latitude 
during the full-glacial may have been related to a relatively fixed 
position of the polar frontal zone at that latitude, separating the 
relatively cold Pacific Airmass from the warm Maritime Tropical Airmass, 
and concentrating cold air, cloudiness, and precipitation along and north 
of that boundary (Delcourt and Delcourt 1983). In that the population 
centers of spruce and fir were not entirely coincident, edaphic and 
orographic factors must also have influenced their previous southward 
migrations, their competitive abilities, and their relative abundances 
across the region. Overall, however, the variability in composition of 



30 



full-glacial boreal forests of the southeastern United States appears to 
be within that of extant boreal forests of eastern Canada (Delcourt and 
Delcourt 1983). 

Late-glacial (14.000 YR BP) 

By 14,000 YR BP, spruce populations had begun to expand along its 
northern boundary as the Laurentide Ice Sheet receded (fig. 4). 

Fir appears to have diminished slightly in dominance and to have begun 
to contract its total range eastward by 14,000 YR BP (fig. 5). At many 
sites, however, fir increased briefly between 13,000 YR BP and 12,000 YR BP 
(not shown in fig. 5). 

Early Holocene (10.000 YR BP) 

By 10,000 YR BP, white spruce had died out in the southwestern portion 
of the mapped area, and in general spruce was becoming restricted in the 
Southeast to the area between the Cumberland and Allegheny Plateaus from 
Tennessee to West Virginia and the Piedmont of the Carolinas and Virginia 
(fig. 4). Dominance of spruce diminished to between 5 and 20% in the 
southern Appalachian region. 

Fir was restricted dramatically in range between 14,000 YR BP and 
10,000 YR BP (fig. 5). Most of the diminishment in southeastern populations 
of fir occurred between 12,000 YR BP and 10,000 YR BP (not shown in fig. 5), 
and it was in that time range that northern populations of balsam fir 
probably separated from southern populations that are today known as Fraser 
fir. In the early Holocene, fir migrated northward in the Appalachians 
at about 250 m per year (Davis 1981). 

Mid -Holocene (6,000 YR BP) 

By the mid-Holocene , spruce was restricted to higher elevations of the 
Cumberland Plateau and the Blue Ridge Province (fig. 4). 

Of the available pollen records, fir was recorded only in Cranberry 
Glades in West Virginia at 6,000 YR BP (Watts 1979), thus appearing in this 
map series (fig. 5) to have migrated northward to the central and northern 
Appalachians by that time. Fir probably also persisted at highest eleva- 
tions of mountain peaks in the southern Blue Ridge Province, but this is 
not yet documented by fossil pollen records. 

Late Holocene (2.000 YR BP) 

By 2,000 YR BP, red spruce was situated on high-elevation peaks and 
mid-elevation intermontane valleys in the southern Appalachians. Although 
locally dominant, overall spruce constituted from 5 to 10% of the forests. 
Spruce began to expand In the northern Appalachian Mountains about 2,000 
YR BP (Davis et al. 1980). 

Fir expanded southward and increased in abundance between 6,000 YR BP 
and 2,000 YR BP, constituting up to 15% of the vegetation of the southern 
Appalachians. 

31 



Post-EuroAmertcan settlement (0 YR RP) 

Today, spruce remains a dominant of high-elevation peaks and 
intermontane valleys (fig. 4). 

Fir is locally dominant at highest elevations in the southern Blue 
Ridge Province (fig. 5). 

Future research 

The available pollen records do not have adequate temporal resolution 
to reflect well the diminishment of populations of spruce and fir resulting 
from widespread logging and blight in the 20th century. Sites such as 
Flat Laurel Gap Bog near Mt. Pisgah and Boone Fork Sphagnum Bog near 
Grandfather Mountain are appropriate for examining the local effects of 
logging upon community composition as reflected in the fossil pollen record. 
Paleoecological sites at lower elevations that record succession during 
the late-glacial/early Holocene transition from boreal to deciduous forests 
can give insight into possible changes in forest composition resulting from 
future elimination of spruce and fir by blight. Paleoecological studies of 
a series of bogs arrayed along topographic and edaphic gradients in the 
Southern Appalachian Mountain Region are currently being investigated in 
order to resolve such fine-scale changes in altitudinal ranges of dominant 
tree taxa and changes in community composition resulting from changing 
climate and geomorphic regimes over the past 18,000 years. 

CONCLUSIONS 

In the northern Appalachians, spruce and fir rapidly colonized newly 
deglaciated land, then their populations stabilized for most of the 
Holocene, and spruce has reexpanded in the past 2,000 years (Davis et al . 
1980). In the central Appalachians, spruce-fir forest replaced tundra 
briefly at the late-glacial/early Holocene transition, then was extirpated 
with Holocene climatic warming, and spruce has recolonized only in the 
late Holocene (Watts 1979). Only in the southern Appalachians are spruce- 
fir forests a true relict ecosystem, persisting continuously over at 
least the past 18,000 years. Over that time span, however, changes have 
occurred in area occupied as well as in floristic composition. Geographic 
isolation from northern populations during the Holocene has resulted in 
elimination of some circumboreal species from the southern Blue Ridge and 
Ridge and Valley provinces (H. Delcourt unpublished data ) and may have 
promoted speciation in other groups. 

Peak warmth of the present interglaclal period occurred by 6,000 YR BP. 
The late Holocene has been characterized by progressive climatic cooling 
and a trend toward re-expansion of spruce-fir forests. This expansion 
presumably would have continued if it were not for modern man's widespread 
alteration of this ecosystem in the southern Appalachians, through exten- 
sive logging, inadvertant introduction of pathogens, possible climatic 
warming following increasing levels of atmospheric CO2, and potential 
impacts of acid precipitation. Fine-scale paleoecological studies can 
help elucidate successional patterns that accompany loss of such dominant 
species and may provide analogs for future changes in forest composition 
within the southern Appalachian Mountain Region. 

32 



LITERATURE CITED 

Barclay, F. H. 1957. The natural vegetation of Johnson County, Tennessee, 
past and present. Ph.D. Dissertation, University of Tennessee, Knoxville, 
Tenn., 147 pp. 

Bernabo, J. C, and Webb, T. III. 1977. Changing patterns in the Holocene 
pollen record of northeastern North America: a mapped summary. Quat. 
Res. 8: 64-96. 

Craig, A. J. 1969. Vegetational history of the Shenandoah Valley, 
Virginia. Geol. Soc. Amer. Spec. Paper 123: 283-296. 

Davis, M. B. 1981. Quaternary history and the stability of forest 
communities. In D. C. West et al. (eds.) Forest succession, concepts 
and application, p. 132-153. N. Y.: Springer-Verlag. 

Davis, M. B., Spear, R. W. , and Shane, L. C. K. 1980. Holocene climate 
of New England. Quat. Res. 14: 240-250. 

Delcourt, H. R. 1979. Late Quaternary vegetation history of the Eastern 
Highland Rim and adjacent Cumberland Plateau of Tennessee. Ecol. 
Monogr. 49: 255-280. 

Delcourt, P. A. 1980. Goshen Springs: late Quaternary vegetation record 
for southern Alabama. Ecology 61: 371-386. 

Delcourt, P. A., and Delcourt, H. R. 1977. The Tunica Hills, Louisiana- 
Mississippi: late glacial locality for spruce and deciduous forest 
species. Quat. Res. 7: 218-237. 

Delcourt, P. A., and Delcourt, H. R. 1979. Late Pleistocene and Holocene 
distributional history of the deciduous forest in the southeastern United 
States. Verttff. Geobot. Inst. ETH, Stiftung RUbel (ZUrich) 68: 79-107. 

Delcourt, P. A., and Delcourt, H. R. 1981. Vegetation maps for eastern 
North America: 40,000 YR B.P. to the present. In R. C. Romans (ed.) 
Geobotany II, p. 123-165. N. Y.: Plenum. 

Delcourt, P. A., and Delcourt, H. R. 1983. Late -Quaternary vegetational 
dynamics and community stability reconsidered. Quat. Res. 19: 265-271. 

Delcourt, P. A., Delcourt, H. R. , Brister, R. C, and Lackey, L. E. 1980. 
Quaternary vegetation history of the Mississippi Embayment. Quat. Res. 
13: 111-132. 

Delcourt, H. R # , Delcourt, P. A., and Splker, E. C. 1983. A 12,000-year 
record of forest history from Cahaba Pond, St. Clair County, Alabama. 
Ecology 64: 874-887. 



33 



Delcourt, P. A., Delcourt, H. R. , and Webb, T. III. (in press ). Atlas of 
mapped distributions of dominance and modern pollen percentages for 
important tree taxa of eastern North America. Amer. Assoc. Strat. 
Palynol. Contrib. Ser. 15: 1-128. 

Dreimanis, A. 1977. Late Wisconsin glacial retreat in the Great Lakes 
region, North America. Ann. New York Acad. Sci. 288: 70-89. 

Emilianl, C. 1972. Quaternary hypsithermals. Quat. Res. 2: 270-273. 

Graham, A. 1973. History of the arborescent temperate element in the 
northern Latin American biota. In A. Graham (ed.) Vegetation and 
vegetational history of northern Latin America, p. 301-314. N. Y.: 
Elsevier. 

King, J. E. 1973. Late Pleistocene palynology and biogeography of the 
western Missouri Ozarks. Ecol. Monogr. 43: 539-565. 

Kolb, C. R., and Fredlund, G. G. 1981. Palynological studies, Vacherie and 
Raybum's Domes, North Louisiana salt dome basin. Inst. Env. Studies, 
La. State Univ., Baton Rouge, Report E530-02200-T-2: 1-50. 

Prentice, I. C. 1982. Calibration of pollen spectra in terms of species 
abundance. In B. Berglund (ed.) Palaeohydrological changes in' the temper- 
ate zone in the last 15,000 years, Vol. Ill, specific methods, p. 25-51. 
Lund: Dept. Quat. Geol, 

Ramseur, G. S. 1960. The vascular flora of high mountain communities of 
the Southern Appalachians. J. Elisha Mitchell Sci. Soc. 76: 82-112. 

Ruddiman, W. F., and Mclntyre, A. 1976. Northeast Atlantic paleoclimatic 
changes over the past 600,000 years. Geol* Soc, Amer. Memoir 145: 111- 
146. 

Shanks, R. E. 1954. Climates of the Great Smoky Mountains. Ecology 
35: 354-361. 

Watts, W. A. 1970. The full-glacial vegetation of northwestern Georgia. 
Ecology 51: 17-33. 

Watts, W. A. 1979. Late Quaternary vegetation of central Appalachia and 
the New Jersey Coastal Plain. Ecol. Monogr. 49: 427-469. 

Watts, W. A. 1980a. The late Quaternary vegetation history of the 
southeastern United States. Ann. Rev. Ecol. System. 11: 387-409. 

Watts, W. A. 1980b. Late -Quaternary vegetation history at White Pond on 
the Inner Coastal Plain of South Carolina. Quat. Res. 13: 187-199. 

Watts, W. A., and Stuiver, M. 1980. Late Wisconsin climate of northern 
Florida and the origin of species-rich deciduous forest. Science 210: 
325-327. 



34 



Whitehead, D. R. 1981. Late -Pleistocene vegetational changes in 
northeastern North Carolina. Ecol. Monogr. 51: 451-471. 

Whit taker, R. H. 1956. Vegetation of the Great Smoky Mountains. Ecol, 
Monogr. 26: 1-80. 



35 



REVIEW OF THE BIOLOGY AND ECOLOGY OF THE BALSAM WOOLLY APHID 
IN SOUTHERN APPALACHIAN SPRUCE-FIR FORESTS 

Christopher Eagar— 

Abstract. The balsam woolly aphid (Adelges piceae Ratz.), native to 
Europe, was introduced into Maine about 1900 and has subsequently spread 
throughout the eastern fir forests. This insect pest was detected on 
Fraser fir ( Abies f raseri [Pursh] Poir.) on Mount Mitchell in North 
Carolina in 1957; however, at that time the entire mountain was infested. 
The aphid was discovered on Roan Mountain in 1962 and in most of the 
other Southern Appalachian fir communities in 1963. Infestations were 
not found on Mount Rogers, Virginia, until 1979, but tree core analysis 
indicated aphid activity since about 1962. Fraser fir on Mount Rogers 
do not succumb to aphid attack as rapidly as Fraser fir from the other 
Southern Appalachian stands. Balsam woolly aphid populations consist 
of wingless females which rely on passive dissemination, with wind 
currents providing the major vector. Reproduction is parthenogenetic , 
and fecundity rates are high. The insect inserts its stylet into the 
bark of the tree and feeds on plant sap within cortical parenchyma 
cells. During the course of feeding, a substance secreted by the insect 
is disruptive to nearby cells and tissue. Tree mortality is due to 
decreased translocation within the xylem, with death occurring in 2-7 
years following initial infestation. Aspects of host-pest interactions, 
as well as the current status and possible air pollution-aphid interaction 
in the rapid death of Fraser fir, are discussed. 

Additional keywords : Abies f raseri , Adelges piceae, Southern Appalachian 
spruce-fir, host-pest interactions. 

INTRODUCTION 

Migration of the balsam woolly aphid ( Adelges piceae Ratz.) into the 
Southern Appalachian spruce-fir forests has concerned scientists, resource 
managers, and recreationalists. This pest is a tiny, sucking insect that feeds 
on the bark of true firs ( Abies spp.), causing mortality much out of proportion 
to its size. Fraser fir (Abies fraseri (Pursh) Poir.) is easily killed by the 
balsam woolly aphid, with the time from initial infestation being between 3 and 
9 years, depending on the size and vigor of the tree (Amman and Speers 1965). 
The intensity of the host reaction combined with the phenomenal reproductive 
potential of the aphid has already created significant changes in the species 
composition and structure of the Southern Appalachian spruce-fir forests. 

The balsam woolly aphid is native to Europe and was first identified in North 
America in 1908 on balsam fir ( Abies balsamea (L.) Mill.) in Maine (Kotinsky 
1916). The insect probably arrived in North America prior to 1900 on imported 
nursery stock, with separate introductions in southern Nova Scotia and Maine 
(Balch 1952). 



—Biological Technician (Ecologist), Uplands Field Research Laboratory, Great 
Smoky Mountains National Park, Gatlinburg, TN 37738. I would like to thank 
R. L. Hay and K. D. Johnson for insight and assistance during initial research 
activities and preparation of information presented in this paper. 

36 



A separate introduction on the west coast of North America resulted in the 
aphid being identified on noble fir ( Abies procera Rehd. ) and grand fir ( Abies 
grandis (Dougl.) Lindl.) near San Francisco in 1928 (Annand 1928). Firs in the 
Willamette Valley were infested by 1930, and by the 1950s the aphid was 
established throughout the Pacific Northwest from the coast to the summit of the 
Cascade Mountains (Mitchell 1966). 

The balsam woolly aphid was first detected in the Southern Appalachians on 
Mount Mitchell, North Carolina, in 1957 (Speers 1958). Subsequent surveys 
revealed that there were 11,000 dead firs and the aphid had spread throughout the 
entire 3,035 hectares of Fraser fir type on Mount Mitchell (Nagel 1959). High 
mortality and widespread aphid distribution indicated aphid establishment prior 
to 1957, perhaps as early as 1940. The Mount Mitchell infestation then spread 
to the Fraser fir communities throughout the Southern Appalachians. 

Balsam woolly aphids could not have chosen to invade a better peak in order 
to further their population expansion. Mount Mitchell, the tallest peak in the 
East, is centrally located to all Fraser fir in the Southern Appalachians. The 
Black Mountains, of which Mount Mitchell is a part, have a north-south 
orientation in an otherwise southwest-northeast oriented chain. Therefore, Mount 
Mitchell is a distinctively tall peak in a continuum of tall peaks, providing 
relatively easy dissemination to the other Southern Appalachian fir stands. 

Balsam woolly aphids were detected in 1962 on Roan Mountain (Ciesla and 
Buchanan 1962), which is located 32 kilometers N 15 E of Mount Mitchell. 
Grandfather Mountain was found to have aphids in 1963; it is 48 kilometers N 50 E 
from Mount Mitchell. The same year, aphids were found on Mount Sterling, which 
is 64.4 kilometers S 85 W of Mount Mitchell (Ciesla et al. 1963). In subsequent 
years, balsam woolly aphids have been found in all Fraser fir stands. 

BIOLOGY AND ECOLOGY OF THE APHID 

The balsam woolly aphid has been placed in the order Homoptera , the 
superfamily Aphidoidea , family Phylloxeridae , and subfamily Adelginae . There are 
11 species of adelgids that infest Abies , all of which are holarctic in origin. 
Two of the 11 species, A. piceae and A. nusslini (Borner), have inadvertently 
been introduced into North America. A. nusslini , indigenous to Europe, has a 
limited distribution in North America, where it has not seriously damaged its 
hosts. In Europe, this species has caused limited economic damage, primarily to 
Abies alba (Miller) (Bryant 1974). A. piceae is innocuous in Europe but it is 
extremely damaging in North America. It is believed that A. piceae evolved from 
A. nusslini following the movement of the latter species from the Caucasion 
region to Europe. In Europe, the two species apparently occupy different 
ecological niches, with A. piceae feeding on the trunk and A. nusslini feeding 
on the twigs and needles (Balch 1952). This pattern has not been observed in 
North America. 

Life Cycle and Development of the Aphid 

the fir adelgids exhibit complex polymorphic life cycles which often include 
alternation of hosts, with spruce ( Picea spp.) being the primary host and the true 
firs ( Abies spp.) being the secondary host. Sexual reproduction is associated 
with the primary host and parthenogenesis with the secondary host. 

37 



Throughout its range, the balsam woolly aphid has evolved the capacity to produce 
successive generations on the secondary host and is not found in sexual or migrant 
form in North America (Balch 1952). Thus populations of the balsam woolly aphid 
in North America consist only of females, and reproduction is parthenogenetic . 

The life cycle of the balsam woolly aphid consists of an egg stage, three 
larval instars, and the adult. The following description of each stage is based 
on examinations made in eastern Canada by Balch (1952) and is consistent with 
observations I have made in the Southern Appalachians. 

Eggs are oval, light purplish-brown, about 0.4 mm long, and are attached 
behind the stationary parent by a silken thread. As the egg matures, the color 
changes to orange-brown. The first instar (neosisten) is the only form capable 
of initiating movement. This "crawler" is about 0.4 mm long with an oval, 
ventrally flattened body. Upon emerging from the egg, its color is light 
orangish-brown. Once a suitable feeding site is located, the stylet is inserted 
into the bark and, following a period of dispause, feeding begins. This 
developing instar becomes purlish-black, and small tufts of wax thread appear on 
its sides. The insect remains at this location for the rest of its life. 

The second instar has a broader body and is about 0.5 mm long. The color 
remains the same as the first instar; however, the entire body becomes covered 
with long, curling, white wax threads which give the balsam woolly aphid its 
characteristic woolly appearance. During this stage the legs and antennae 
atrophy. The third instar is about 0.65 mm long with all other characteristics 
similar to the second instar. 

Adults have a hemispherical body that is slightly longer than it is wide. The 
color is still purplish-black and the aphid is about 0.8 mm long. By this time, 
the wax threads have reached their maximum development and provide easy 
recognition. 

Balsam woolly aphid populations in North America produce a minimum of two 
generations per year. The overwintering generation is called the hiemosistens , 
and the generation that completes its life cycle during the summer is known as the 
aestivosistens . There is little biological or morphological difference between 
the two generations. 

Hiemosistens . All life stages from eggs to adults have been observed in late 
autumn; however, only the first instar larvae that have inserted their stylets 
and become dormant survive the winter. Insect activity begins when the host tree 
starts its annual growth cycle, but not all aphids begin feeding at the same time. 
Balch (1952) reported 20 days variation between individuals in the time that 
aphids broke dormancy on the same tree. In the Southern Appalachians, Amman 
(1962) found that dormant first instars began feeding as early as April 10 and as 
late as May 15 during the 1960 growing season. 

After feeding begins in the spring, the first adults occur during May and early 
June. Reproduction begins when the adult is 2 or 3 days old and continues for at 
least 5 weeks. Eggs require about 9 to 12 days of incubation, but that will vary 
according to temperature and humidity (Balch 1952, Amman 1968, Greenback 1970). 

Aestivosistens . Within a few hours of hatching, the first instar of the 
aestivosistens usually finds a suitable feeding site close to the parent. Two or 
three days after the stylet is inserted into the bark, the aphid enters diapause 



JO' 



for a duration of 3 to 8 weeks. Aestivosistens complete their metamorphosis 
during August and September. First instar larvae produced by aestivosistens that 
are in a dormant stage at the appropriate time in autumn and successfully 
overwinter make up the hiemosistines of the next growing season. 

Reproductive Potential . Balsam woolly aphid reproductive rates are influenced 
by the weather conditions throughout the entire life cycle of the insect, the 
vigor and age of the host tree, the amount of protection provided at the feeding 
site, and the individual aphid (Greenbank 1970; Amman 1970). Balch (1952) 
reported that the hiemosistens averaged about 100 eggs per adult with a maximum 
of 248 and that the aestivosistens averaged about 50 eggs per adult with a 
maximum of 105 eggs. Survival rates will vary with environmental and host factors 
but average about 60 percent for both generations. 

Dispersal of the Aphid . Being wingless and, except for the first instar, 
incapable of active travel, the balsam woolly aphid is dependent on passive forms 
of movement. The principal dispersal vector for the balsam woolly aphid is air 
currents. Crawlers, and occasionally eggs, are readily transported by wind. 
Balch (1952) found that they were transported more than 90 m by surface winds and 
several kilometers by vertical air currents in eastern Canada. In the 
mountainous Southern Appalachians, wind has been responsible for the movement of 
the aphid up to distances of 64 km (Amman 1966). 

In addition to being the primary means of balsam woolly aphid dissemination 
among the spruce-fir islands of the Southern Appalachians, wind plays an 
important role in the pattern of infestation development within each islands. 
Initial infestation on prominent mountain masses in the Great Smoky Mountains was 
located at the lower elevational limits of Fraser fir. On mountains with a longer 
history of balsam woolly aphid activity, dead trees occurred at low to middle 
elevations (1300 to 1700 m) . This was followed by a zone of heavy infestation 
with variable mortality, and then by a gradual decrease in infestation intensity 
with increasing elevation to the summit (Eagar 1978). Johnson (1977) found that 
the largest Fraser firs in a stand supported the highest aphid populations. From 
their tall crowns, these trees provided optimum loci to spread infestations 
upslope. The behavior of wind in mountain landscapes explains this pattern. 

As an air mass approaches a physical obstruction, such as a mountain or large 
ridge, the air is forced to rise toward the summit. The air mass above the 
mountain is essentially unaffected by the obstruction and maintains its original 
speed and direction vector. Thus, air that is forced up by the mountain is 
restricted to less space, forcing a major air speed increase as the mountain 
summit is passed. On the leeward side, air pressure is lower, so the speed slows 
and the air mass falls through a series of eddies. The stronger the wind, the 
larger the eddy and the more force within the eddy (Schroeder and Buck 1970). 
During June and September these winds are laden with balsam woolly aphid crawlers 
and occasional eggs. The wind speed at the windward side at the summit is too 
great for the deposition of crawlers within the forest canopy. If by chance they 
should encounter a tree crown, they probably would not survive the collision. 
However, on the leeward side of the mountain, the aphid-laden air slows within the 
eddy, thereby providing a high probability of successful insect deposition. If 
the crawler lands in or near a Fraser fir, a new infestation has begun. 

Other means of dispersal are gravity, the primary manner in which fir 
seedlings and sapling become infested; humans, by unknowing transport of crawlers 

39 



or eggs on clothes or vehicles; nursery stock or Christmas tree commerce; and 
phoresy — transport by animals. 

Ecology and Population Dynamics of the Aphid 

Environmental Factors. High ambient air temperatures are not fatal to the 
balsam woolly aphid (Balch 1952). In fact, consistently warmer than normal 
temperatures within a region would benefit the population. The increased 
developmental rate induced by the warmer temperature could increase the number 
of generations per year, which would greatly add to the growth of the population. 
However, high bark surface temperatures, caused by direct sunlight en a darkened 
object, are fatal to the adult and all nymphal stages. The cause of death is 
desiccation (Balch 1952). The second and third instars as well as the adult are 
afforded some protection from solar radiation by the wool that covers their 
bodies. Death of aphids due to exposure to direct sunlight is insignificant in 
terms of overall population dynamics. 

Extremely cold temperatures limit population growth in the more northerly 
latitudes but is not a factor in the Southern Appalachians. All aphid stages 
except the overwintering first instar are killed by prolonged exposure to 
temperatures below C and instantly by temperatures below -20 C (Balch 1952, 
Greenbank 1970). Overwintering first instars require a period of gradual exposure 
to colder temperatures in order to develop cold-hardiness before they can 
withstand extremely low temperatures of -25 C to -34 C. Amman (1967) reported 
that an overnight temperature of -34 C on Mount Mitchell, North Carolina, caused 
higher than normal mortality, but there was no indication that significant control 
of aphid populations would result from these rare low temperatures in the 
Southern Appalachians. Under normal weather conditions, all aphid stages have 
adaptations which enhance their survival. 

Biotic Factors . The balsam woolly aphid in North America is free of damaging 
parasites and diseases. Introductions in eastern Canada, the Pacific Northwest, 
and the Southern Appalachians of foreign and native insect predators of the aphid 
had little effect on population dynamics (Balch 1952, Brown and Clark 1970, Amman 
1961, Mitchell and Wright 1967, Amman 1970, Amman and Speers 1971). Ineffective 
synchronization of predator-prey life cycles, poor searching ability of the 
predators, the high reproductive capacity of the balsam woolly aphid, and the 
rapid death of the host tree were all factors in the failure of predators to 
reduce aphid populations. 

The carrying capacity of the host tree is the only biotic factor that 
significantly affects the upper limits of aphid populations in the Southern 
Appalachians. This carrying capacity is surpassed in a comparatively short 
time, resulting in a sharp reduction in the aphid population followed by 
death of the host (Amman 1970). 

Applied Factors . Lindane (gamma isomer of benzene hexachloride) has been 
the primary chemical for the control of the balsam woolly aphid; however, it is 
of little practical use in forest conditions since the bole of the tree must be 
sprayed from within the stand to the point of saturation. Lindane has been 
used to protect critical high-use recreation areas on Mount Mitchell during the 
1960s (Ciesla et al. 1963) and on Roan Mountain beginning in 1971 (Ward et al. 
1973; Johnson et al. 1980). At both locations, spraying involved application of 
1/8 percent lindane within a 200-f oot-wide zone on both sides of the primary 

40 



access roads. The use of indane has come under increased scrutiny by the 
Environmental Protection Agency due to is persistence within the environment. 
Nash and Woolson (1967) reported a 10 percent average residue in the soil 14 
years after application of 56 and 224 kg/ha for several soil types at 
Beltsville, Maryland. Lindane is broken down within the soil by 
microorganisms (MacRae et al. 1967). An evaluation on Mount Mitchell showed 
high initial concentrations in the litter layer, followed by slow movement 
into the soil with a peak concentration at 1.5 years after application 
(Jackson et al. 1974). Tests for lindane in animals and stream water on Mount 
Mitchell were negative. 

Other chemicals which have been shown effective in killing larval and 
adult balsam woolly aphids under field conditions are propoxur (Baygon), 
permethrin (Ambush and Pounce), chlorpyrifos (Dursban), and chlorpyrif os- 
methyl (Reldan) (Hopewell and Bryant 1969; Hastings et al. 1979; Puritch et 
al. 1980). As with lindane, these insecticides must be applied from within the 
stand to each individual stem. Most also have limited ovicidal effect, 
thereby necessitating multiple applications each year. Several of these 
compounds are toxic to birds and mammals, and their use in natural areas is 
restricted. 

An alternative to the use of highly toxic and/or persistent petro- 
chemicals is the potassium salt of oleic acid (Puritch 1975). Fatty acids are 
natural constituents of plants and animals, are biodegradable, and, when used 
properly, are low in phytotoxicity . They have biocidal effect on certain soft- 
bodied insects, including the balsam woolly aphid. The exact mechanism of 
death is not certain, but it seems to be associated with the disruption of 
oxidative phosphorlation within individual cells and the alteration of cell 
membrane permeability (Puritch 1975). One additional favorable property of 
potassium oleate for use on the balsam woolly aphid is that it causes the loss 
of hydrophobic properties of the wax secretions (wool) on the insect's body, 
thereby allowing better contact with the body. The limiting factors in its 
use are the mode of application, which is similar to the above, and its lack 
of residual activity. 

Potassium oleate ( Insecticidal Soap) is currently being used in Great 
Smoky Mountains National Park (GRSM) around the Clingmans Dome parking lot and 
paved trail to the observation tower. The effectiveness of this limited 
control program is being monitored by 16 permanent plots established 
throughout the control zone by the GRSM Resources Management Division. 
Initial observations indicated that high levels of aphid mortality are 
achieved after each application. However, many trees around the parking lot 
have died because of several years of heavy infestation prior to control 
efforts. The U.S. Forest Service is also experimenting with the use of 
potassium oleate on Roan Mountain, but Lindane continues to be the primary 
insecticide (Pat Berry, personal communication). 

Balsam Woolly Aphid - Fir Interactions 

Feeding balsam woolly aphids initiate anatomical and biochemical changes 
within the host that produce physiological modifications resulting in death 
of the tree. The anatomical changes have been documented, but the 
biochemical mechanisms remain less clear. Lack of a culture technique for the 
insect in the laboratory has delayed analysis of the salivary secretions 
injected into the tree. Determination of the chemistry of these secretions 

41 



is necessary for an understanding of the biochemical basis of damage to the 
tree. 

The reaction of North American Abies to balsam woolly aphid feeding is 
manifest through microscopic symptoms, which deal with the response of cells 
near the feeding sites, and the macroscopic symptoms, including growth and 
form changes. 

Microscopic Symptoms . The stylet of the balsam woolly aphid, which is 
about four times as long as the body, penetrates the bark intercellularly 
through the phellem and into the phelloderm, where the insect feeds in 
parenchyma. During feeding, the stylet is partially withdrawn and reinserted; 
its direction is apparently determined by aphid senses and not solely by the 
path of least resistance (Balch 1952). 

Following the insertion of the stylet, the first instar nymph enters 
diapause. Prior to diapause, a salivary substance secreted from the tip of 
the maxillae forms a sheath around the stylet. This slivary substance is also 
secreted during feeding; its probable purpose is the modification of the 
feeding site in a manner that facilitates the uptake of needed nutrients 
(Auclair 1963; Balch et al. 1964; Miles 1968). These secretions also result 
in damage to cortical parenchyma cells around the feeding site. The saliva 
produces abnormal cell development around the stylet through either an 
enzymatic or synergistic action with grown hormones and inhibitors secreted 
by the aphid or already present in the host tree (Balch et al. 1964). Cortical 
parenchyma cells are enlarged six or seven times more than normal, cell walls 
are thickened, and the cell nuclei become larger. This process is closely 
followed by hyperplasia in the surrounding parenchyma and, sometimes, the 
formation of a secondary phellogen, which is the initial stage in the wound- 
healing process (Balch 1952, Saigo 1976). Not all Abies in North America are 
able to complete this process, whereas European silver fir ( Abies alba (L.) 
Mill.), which has evolved with the aphid, is able to effectively seal off the 
feeding area with wound periderm before the tree suffers irreversible damage 
(Kloft 1957). 

In a study of the effect of plant hormones on wound periderm formation 
in Fraser fir, Eagar (unpublished data) found that small wounds in the bark 
of Fraser fir combined with a one-time injection of two auxin-like compounds 
( indole-3-acetic acid and napthaleneacetic acid), a possible component of 
aphid saliva, required 11 additional days for secondary phellogen formation 
than the controls of wounding only and wounding and injection of distilled 
water. Treatments utilizing a gibberellin and a cytokinin formed secondary 
phellogen at the same rate as the controls. The hypersensitivity of Fraser 
fir in GRSM may be, in part, due to a disruption of the normal plant defense 
mechanisms by plant growth substances secreted by the balsam woolly aphid. 
(See Mullick 1977 for a review of plant defense mechanisms.) Although the 
chemical content of the saliva of the balsam woolly aphid has not been 
determined, analysis of the saliva of other parenchyma and phloem feeders has 
consistently found auxin-like compounds (Miles 1968). The inability of Fraser 
fir to seal off the feeding site and contain the aphid secretions results in 
additional plant tissue damage described below. 

Diffusion of balsam woolly aphid secretions results in cellular changes 
within the phloem, vascular cambium, and xylem. The phloem of infested grand 

42 



fir (Abies grandis (Dougl.) Lindl.) contained more tangential bands of phloem 
parenchyma strands and fiber schlareids and had a high number of traumatic 
resin ducts and shorter sieve cells than unifested trees (Saigo 1969). The 
vascular cambium of infested grand fir contained a wider radial file of cells 
and increased periclinal and anticlinal division of furiform initials compared 
to uninfested trees (Smith 1967). The cellular characteristics displayed by 
the xylem are similar to those of compression wood: short, thick, highly 
lignified, reddish tracheids; an increase in the number of rays; checks in the 
secondary cell walls at a larger angle to the longitudinal axis than normal; 
and a large reduction in the lumen (Balch 1952, Doerksen and Mitchell 1965, 
Foulger 1968). Abies alba in Scotland did not exhibit these symptoms (Varty 
1956). 

Balch (1952) and Mitchell (1967) observed that the movement of aqueous 
solutions of dye through the wood of balsam woolly aphid infested trees was 
restricted to fewer annual rings and transported slower than in normal wood. 
Puritch (1971) quantified these differences and found that balsam woolly aphid 
infestations reduced the permeability of sapwood by 95 percent, a value which 
approximates the permeability of heartwood. Although some tracheids were 
aspirated, the main cause of decreased permeability was a reduction in the 
number of conducting bordered-pit pairs due to encrusting of the perforations 
on bordered-pit membranes of the sapwood; a condition similar to that of 
heartwood (Puritch and Petty 1971, Puritch and Johnson 1971). Additionally, 
the phenolic composition of balsam woolly aphid affected sapwood was similar 
to normal heartwood (Puritch 1977). Thus balsam woolly aphid infestation 
causes the formation of premature heartwood which results in greatly reduced 
translocation of water and minerals to the crown, resulting in water stress 
and causing death of the tree due to reduction of photosynthesis to near zero 
(Puritch 1973). 

Macroscopic symptoms . Two types of macroscopic changes are associated 
with balsam woolly aphid attack: those due to infestations being concentrated 
in the crown, or those on the central stem of the host tree. Crown 
infestations exhibit the following sequence of external symptoms: (1) swelling 
at the nodes, (2) shoots becoming thickened and irregularly twisted and often 
turning downward, (3) tip inhibition, (4) defoliation, and (5) dieback (Balch 
1952). 

The loss of height growth combined with the slight increase in diameter 
growth associated with light to moderate infestations produces extreme stem 
taper. Crown infestations can cause death of the host after 10 to 20 years 
of aphid activity. Recovery and resumption of normal growth have been 
reported for balsam fir in Newfoundland (Schooley 1976). 

Macroscopic symptoms of stem infestations are not outwardly apparent 
prior to the death of the tree. Characteristics of stem infestations include 
a brief period of increased diameter growth followed by 1 or 2 years of 
reduced diameter growth. The tree dies rapidly, as manifested by the gradual 
change in foliage color from healthy blue-gree to a faded yellow-green, to a 
bright rusty-red, and finally to dead-brown. The aphid population crashes 
prior to the completion of change in foliage color (Amman and Talierco 1967, 

43 



Amman 1970). This sequence is influenced by the amount and frequency of 
rainfall during the growing season. Summers with low rainfall or extended 
periods (2-3 weeks) without rainfall produce the above sequence. However, 
during summers of adequate rainfall, many aphid infested Fraser fir do not 
exhibit the final color changes to rusty-red and brown. Instead, the needles 
stop at yellow-green and fall off throughout the summer. 

Fraser fir growing in the Southern Appalachians which are larger than 4 
cm dbh have stem infestations. Trees smaller than this exhibit signs of 
gouting and bud inhibition common to crown infestations. Small Fraser fir 
saplings and seedlings do not build up large populations of balsam woolly 
aphids. In examining thousands of small, understory fir in GRSM over the past 
8 years, I have not found reproducing adults on trees less than 1.5 m tall. 

It is likely, but untested, that young or very small, suppressed, older 
Fraser fir lack either the proper compounds or sufficient concentration of 
compounds needed by the insect to produce the moulting and juvenile hormones 
required for normal development. (See Beck and Reese 1976 and references 
therein for a general review of the chemistry of insect-plant interactions.). 
Appreciable mortality of young or small saplings occurs only under heavy 
overstory infestations. Recovery of young trees does occur, if they have not 
been too badly damaged, once the overstory dies and the rain of insects to the 
understory stops. 

Patterns of Aphid Infestations 

Within an infested stand, canopy position and the degree of stress from 
competition determine infestation pattern and mortality rates of individual 
trees (Johnson 1977). Large trees, with their crowns exposed to air currents, 
are the first to become infested and support large populations for several 
years prior to death. However, suppressed trees with dbh >4 cm are the first 
to succumb, although insect numbers on individual trees are constantly low. 
Trees of intermediate size are the last to die within a stand, probably as 
a result of becoming infested after the canopy dominates in combination with 
better vigor than suppressed trees. 

Infestation patterns along an individual bole are dependent on the vigor 
of the tree, stand density, tree size, and morphological features of the bark 
surface. Vigorous trees with live crown ratios greater than 50 percent will 
develop insect population along the entire bole, with the highest numbers at 
the base of the crown. Insect populations on trees growing under average or 
high stand densities do not develop down low on the bole but occur mainly at 
the base of and just within the crown. Few insects occur on the portion of 
the stem in the upper third of the crown, regardless of stand conditions or 
growth form (Eagar, unpublished data). Thus it is often difficult to detect 
the presence of balsam woolly aphids by observations made at eye level, 
particularly in areas of early aphid infestation development. Bark surface 
features associated with high aphid populations are high densities of 
lenticels and development of a rough-textured, furrowed bark but not a thick, 
plate-like bark (Eagar, unpublished data). The balsam woolly aphid apparently 
cannot physically penetrate the tight, smooth, grey bark of young stems. 

The only indication of possible resistance of Fraser fir to balsam woolly 
aphid attack has been found on Mount Rogers, Virginia. It had been thought 
that Fraser fir on Mount Rogers were free of balsam woolly aphids prior to 
detection of two small infestations on Cabin Ridge in 1979 by the USDA Forest 

44 



Service, Forest Pest Management Division. Subsequent stem analysis of several 
trees within the infestation revealed aphid-caused redwood in the annual rings 
beginning in 1962 (H. Lambert, personal communication). Monitoring of insect 
populations on individual trees by USDA Forest Service personnel over the next 
2 years indicated a pattern of aphid population buildup and collapse. I 
observed the bark of trees in this stand and found it to be much hardened and 
having a thicker rhytidome than uninfested trees on Mount Rogers or infested 
trees in the Great Smoky Mountains. Histological examination of bark tissue 
from infested trees on Mount Rogers showed numerous small pockets of dead 
tissue with wound periderm within the cortex, which may have been sealed-off 
aphid feeding sites. These pockets, the thickened hard rhytidome, and the long 
history of the infestation without significant spread or mortality suggest a 
genetically based ability to rapidly form wound periderm around aphid feeding 
sites which prevents the diffusion of the harmful secretions into the xylem. 

(NOTE: This mechanism is based on a few observations and should be 
investigated with appropriate experimental design prior to acceptance.) 

CURRENT STATUS AND FUTURE CONSIDERATIONS 

The initial wave of balsam woolly aphid caused mortality of Fraser fir 
in the southern Appalachians is nearly completed. A few small stands with 
healthy but infested fir are located in the vicinity of Clingmans Dome in 
GRSM. The fir growing in the protection zones on Roan Mountain (about 162 ha) 
and Clingmans Dome (about 10 ha) and the fir on Mount Rogers have not been 
significantly harmed by the aphid. The area that had been protected on Mount 
Mitchell until 1974 is now heavily infested, and significant mortality is 
beginning to occur. Without a major breakthrough in development of an 
inexpensive, fairly specific, aerially applied insecticide, the balsam woolly 
aphid will continue to be a significant pest in the spruce-fir forests of the 
Southern Appalachians. 

On Mount Sterling in the Great Smoky Mountains, the understory fir that 
survived the initial infestation and those that have grown from seed since then 
are now approaching an age that can support balsam woolly aphid populations. 
Fraser fir outside the control area on Clingmans Dome, located at the opposite 
end of the fir distribution in the Great Smoky Mountains from Mount Sterling, 
are just now becoming infested. The prevailing winds blow from Clingmans Dome 
to Mount Sterling; thus, the return trip will be faster than the initial 
infestation spread. It seems likely that a cyclic situation will develop: 
initial infestation + limited recovery and regeneration -+■ reinf estation, etc. 
The length of time for one complete cycle in the Great Smoky Mountains can only 
be speculated but appears to be on the order of 35 to 60 years. 

In addition to loss of all overstory and a significant part of the 
understory Fraser fir, Southern Appalachian spruce-fir communities will 
experience more subtle changes due to secondary responses. The portion of the 
flora which is adapted to moist, cool, low-light environments will loose a 
sizable part of its habitat. Boner (1979) sampled stands of various lengths 
of time since balsam woolly aphid damage and found that in stands with long 
histories of activity there was a significant increase in blackberry ( Rubus 
canadensis ) and a decrease in moss, viburnum (Viburnum alnifolium), and 
Vaccinium cover. (See DeSelm and Boner, this Proceedings.). 

45 



Within GRSM, 131 permanent plots (10 m x 10 m) were established in 1976 
and 1977 through a contract with the University of Tennessee (Hay et al. 1978) 
in order to evaluate forest dynamics in response to aphid-caused disturbance. 
There are still important components of the spruce-fir ecosystem which are not 
being evaluated with respect to impacts due to loss of Fraser fir. These areas 
include mammals, birds, herpetofauna, arthropods, lichens, and fungi. As 
covered in other papers in this publication, many taxa in these groups have 
very specific habitat requirements which are unique to spruce-fir ecosystems. 

In addition to the community structural aspects of balsam woolly aphid 
impact in Southern Appalachian spruce-fir forests discussed above, more subtle 
impacts will probably occur at the functional level. These include alterations 
in decomposition and mineralization rates (Gorham et al. 1979), disruption of 
steady state biogeochemical cycles in old-growth forests or reversal of 
nutrient accumulation in aggrading successional forests (Bormann and Likens 
1979), and a net loss of nutrients from the ecosystem. These changes in 
functional attributes may be much more dramatic in Southern Appalachian spruce- 
fir forests which experienced significant disturbance from turn-of-the-century 
logging than in undisturbed old-growth forests. The result in both types of 
forests would be reduced productivity of subsequent plant communities. 

A final consideration of the interaction of balsam woolly aphid with 
Fraser fir concerns the role of atmospheric pollution. Of particular initial 
interest are questions of how atmospheric pollutants may predispose or 
accelerate the death of Fraser fir by balsam woolly aphid infestation. More 
specifically, interactive effects between pollutant-induced stress of Fraser 
fir and aphid-caused mortality are suspected but untested. 

Information of this nature is particularly relevant since Fraser fir is 
the most sensitive of North American Abies to aphid attack (Bryant 1974). 
Balsam woolly aphid infestations in the Northeast and Pacific Northwest have 
progressed no farther inland than 100 miles from the respective coasts, which 
are assumed to be the location of initial introduction. Cold winter 
temperatures in these environments are prohibiting further aphid spread (Balch 
1952). These coastal locations also probably experience a diluting of 
atmospheric pollution by frequent mixing of oceanic and continental air. 
Prevailing winds in the Pacific Northwest are almost exclusively from the 
west. Isopaths of weighted average annual pH of precipitation in the East show 
near normal (5.60) values for New Brunswick and Nova Scotia, Canada (Likens 
1976), the regions of highest aphid activity in the Northeast. Of all firs 
infested by the balsam woolly aphid, only Fraser fir grows in an area which 
experiences potentially harmful levels of atmospheric pollution (Skelly et al. 
1970; Uplands Field Research Laboratory, unpublished data). 

Studies based on the hypothesis that air pollutants are involved in the 
comparatively rapid death of Fraser fir following balsam woolly aphid 
infestation are currently being investigated at the University of Tennessee, 
Knoxville (E. E. C. Clebsch and C. Eagar). This study will also seek to 
determine the sensitivity of Fraser fir seedlings to ozone, sulfur dioxide, 
and combinations of the two. An understanding of the degree of air pollution 
impact on Fraser fir seedlings is necessary to evaluate the future probable 
stand dynamics within the spruce-fir ecosystem, given the potential for cyclic 
disturbance by balsam woolly aphid infestation. 

46 



REFERENCES CITED 

Amman, G. D. 1961. Predator introductions for control of balsam woolly aphid on 
Mount Mitchell, North Carolina. USDA Forest Service, SE For. Exp. Stn. Res. 
Note 153. 2 p. 

Amman, G. D. 1962. Seasonal biology of the balsam woolly aphid on Mt . Mitchell, 
North Carolina. J. Econ. Entomol. 55:96-98. 

Amman, G. D. 1966. Some new infestations of balsam woolly aphid in North America, 
with possible modes of dispersal. J. Econ. Entomol. 59:508-511. 

Amman, G. D. 1967. Effect of -29 F. on over-wintering populations of the balsam 
woolly aphid in North America. J. Econ. Entomol. 60:1765-1766. 

Amman, G. D. 1968. Effects of temperature and humidity on development and hatching 
of eggs of Adelges piceae. Ann. Entomol. Soc. Am. 61:1606-1611. 

Amman, G. D. 1970. Phenomena of Adelges piceae populations ( Homoptera : 
Phylloxeridae) in North Carolina. Ann. Entomol. Soc. Am. 63:1727-1734. 

Amman, G. D. , and C. F. Speers. 1965. Balsam woolly aphid in the Southern 
Appalachians. J. For. 63:18-20. 

Amman, G. D. , and C. F. Speers. 1971. Introduction and evaluation of predators 
from India and Pakistan for control of the balsam woolly aphid. Can. Entomol. 
103:528-533. 

Amman, G. D. , and R. L. Talierico. 1967. Symptoms of infestation by balsam woolly 
aphid displayed by Fraser fir and bracted balsam fir. Res. Note SE-85, USDA 
Forest Service, SE For. Exp. Stn. 7 p. 

Annand, P. N. 1928. A contribution toward a monograph of the Adelginae 

( Phylloxeridae ) of North America. Stanford University Press, Palo Alto, CA. 
146 p. 

Auclair, J. L. 1963. Aphid feeding and nutrition. Ann. Rev. Entomol. 8:439-490. 

Balch, R. E. 1952. Studies of the balsam woolly aphid, Adelges piceae (Ratz.), 
and its effects on balsam fir Abies balsamea (L.) Mill. Can. Dept. of Agric. 
Publ. #867. 76 p. 

Balch, R. E., J. Clark, and J. M. Bonga. 1964. Hormonal action in production of 
tumors and compression wood by an aphid. Nature 202:721-722. 

Beck, S. D., and J. C. Reese. 1977. Insect-plant interactions: nutrition and 
metabolism. In F. A. Loewns and V. C. Runeckles, eds. Recent advances in 
phytochemistry. Vol. 11, p. 41-92. 

Boner, R. R. 1979. Effects of Fraser fir death on population dynamics in Southern 
Appalachian boreal ecosystems. M.S. Thesis. Univ. Tennessee, Knoxville. 
105 p. 

Bormann, F. H. , and G. E. Likens. 1979. Pattern and process in a forested 
ecosystem. Springer-Verlag, New York. 

47 



Brown, W. R. , and R. C. Clark. 1960. Studies of predators of the balsam woolly 
aphid, Adelges piceae (Ratz.) ( Homoptera ; Adelgidae ) VIII. Syrphidae (Diptera). 
Can. Entomol. 92:801-811. 

Bryant, D. G. 1974. A review of the taxonomy, biology and importance of the 
adelgid pests of true firs. Can. Environ., Forest Service, NFLD For. Res. 
Centre. No. N-X-lll. 50 p. 

Ciesla, W. M. , and W. D. Buchanan. 1962. Biological evaluation of balsam woolly 
aphid, Roan Mtn. Gardens, Toecane District, Pisgah National Forest, North 
Carolina. USFS, SA. S & PF, Div. FPM. Rep. 62-93 (unpublished). 

Ciesla, W. M., H. L. Lambert, and R. T. Franklin. 1963. The status of the balsam 
woolly aphid in North Carolina and Tennessee. USFS, S & PF, Div. FPM, Asheville, 
NC. Rep. No. 1-11-63 (unpublished). 

Doerksen, A. K. , and R. G. Mitchell. 1965. Effects of balsam woolly aphid on the 
wood anatomy of some western true firs. For. Sci. 11:181-188. 

Eagar, C. C. 1978. Distribution and characteristics of balsam woolly aphid 
infestations in the Great Smoky Mountains. M.S. Thesis. Univ. Tennessee, 
Knoxville. 72 p. 

Foulger, A. N. 1968. Effect of aphid infestations on the properties of grand fir. 
For. Prod. J. 18:43-47. 

Greenbank, D. 0. 1970. Climate and ecology of the balsam woolly aphid. Can. 
Entomol. 102:546-578. 

Gorham, E., P. M. Vitousek, and W. A. Reiners. 1979. The regulation of chemical 
budgets over the course of terrestrial ecosystem succession. Annu. Rev. Ecol. 
Syst. 10:53-84. 

Hastings, F. L. , P. J. Barry, and I. R. Ragenovich. 1979. Laboratory screening 
and field bioassays of insecticides for controlling the balsam woolly aphid 
( Adelges piceae ) in Southern Appalachian fir ( Abies f raseri ) . USDA Forest 
Service Res. Note SE-279. 3 p. 

Hay, R. L. , C. C. Eagar, and K. D. Johnson. 1978. Fraser fir in the Great Smoky 
Mountains National Park: Its demise by the balsam woolly aphid ( Adelges piceae 
Ratz.). Contract Rep., National Park Service, SE Region, Atlanta. 125 p. 

Hopewell, W. W. , and D. G. Bryant. 1969. Chemical control of Adelges piceae 
( Homoptera : Adelgidae ) in Newfoundland, 1967. Can. Entomol. 101:1112-1114. 

Jackson, M. D. , T. J. Sheets, and C. L. Moffett. 1974. Persistence and movement 
of BHC in a watershed, Mt. Mitchell State Park, North Carolina, 1967-72. Pestic. 
Monitoring J. 8:202-208. 

Johnson, K. D. 1977. Balsam woolly aphid infestation of Fraser fir in the Great 
Smoky Mountains. M.S. Thesis. Univ. Tennessee, Knoxville. 64 p. 

Johnson, K. D. , H. L. Lambert, and P. J. Barry. 1980. Status and post-suppression 
evaluation of balsam woolly aphid infestations on Roan Mountain, Toecane Ranger 
District, Pisgah National Forest, North Carolina. Forest Insect and Disease 

48 



Manage. Rep. No. 80-1-13, SE Area State and Private Forestry, USDA Forest 
Service, Atlanta, GA. 

Kloft, W. 1957. Further investigations concerning the interrelationship between 
bark condition of Abies alba and infestation by Adelges piceae typica and A. 
nusslini schneideri. Z. Angew. Entomology 41:438-442. 

Kotinsky, J. 1916. The European fir trunk louse, Chermes ( Dreyf usia ) piceae 
Ratz.). Entomol. Proc. Soc. Washington. 18:14-16. 

Likens, G. E. 1976. Acid precipitation. Chem. Eng. News 54:29-44. 

MacRae, I. C., K. Raghu, and T. F. Castro. 1967. Persistence and biodegradation 
of four common isomers of benzene hexachloride in submerged soils. J. Agric. 
Food Chem. 15:911-914. 

Miles, P. W. 1968. Insect secretions in plants. Annu. Rev. Phytopath 6:137-164. 

Mitchell, R. G. 1966. Infestation characteristics of the balsam woolly aphid in 
the Pacific Northwest. USDA Forest Service Res. Paper PNW-35. 18 p. 

Mitchell, R. G. 1967. Translocation of dye in grand and subalpine firs infested 
by the balsam woolly aphid. USDA Forest Service Res. Note PNW-46 . 17 p. 

Mitchell, R. G., and K. H. Wright. 1967. Foreign predator introduction for control 
of the balsam woolly aphid in the Pacific Northwest. J. Econ. Entomol. 60:140- 
147. 

Mullick, D. B. 1977. The non-specific nature of defense in bark and wood 

during wounding, insect and pathogen attack. In F. A. Loewns and V. C. Runeckles 
eds. Recent advances in phytochemistry , Vol. 11 , p. 395-442. 

Nagel, W. P. 1959. Forest insect conditions in the Southeast during 1958. 
U.S. Forest Service, Stn. Paper SE-100. 10 p. 

Nash, R. G., and E. A. Woolson. 1967. Persistence of chlorinated hydrocarbon 
insecticides in soils. Science 157:924-927. 

Purtich, G. S. 1971. Water permeability of the wood of grand fir ( Abies grandis 
(Doug.) Lindl.) in relation to infestation by the balsam woolly aphid, Adelges 
piceae (Ratz.). J. Exp. Bot. 22:936-945. 

Purtich, G. S. 1973. Effect of water stress on photosynthesis, respiration and 
transpiration of four Abies species. Can. J. For. Res. 3:293-298. 

Puritch, G. S. 1975. The toxic effects of fatty acids and their salts on the 
balsam woolly aphid, Adelges piceae (Ratz.). Can. J. For. Res. 5:515-522. 

Puritch, G. S. 1977. Distribution and phenolic composition of sapwood and 

heartwood in Abies grandis (Doug.) Lindl. and effects of the balsam woolly aphid. 
Can. J. For. Res. 7:54-62. 

Puritch, G. S., and R. P. C. Johnson. 1971. Effects of infestation by the balsam 
woolly aphid, Adelges piceae (Ratz.), on the ultrastructure of bordered-pit 
membranes of grand fir, Abies grandis (Day.) Lindl. J. Exp. Bot. 22:953-958. 

49 



Puritch, G. S., P. L. Nijan, and J. R. Carrow. 1980. Chemical control of 
balsam woolly aphid ( Homoptera : Adelgidae )on seedlings of Abies amabilis . 
J. Entomol. Soc. Brit. Columbia 77:15-18. 

Puritch, G. S., and J. A. Petty. 1971. Effect of balsam woolly aphid, 

Adelges piceae (Ratz.), infestation on the xylem of Abies grandis (Doug.) 
Lindl. J. Exper. Bot. 22:946-952. 

Saigo, R. H. 1969. Anatomical changes in the secondary phloem of grand fir 
( Abies grandis (Dougl.) Lindl.), induced by the balsam woolly aphid 
(Adelges piceae Ratz.). Ph.D. Dissert. Oregon State Univ., Corvallis. 
91 p. 

Saigo, R. F. 1976. Anatomical changes in the secondary phloem of grand fir 
(Abies grandis) induced by the balsam woolly aphid ( Adelges piceae) . Can. 
J. Bot. 54:1903-1910. 

Schooley, H. 0. 1976. Recovery of young balsam fir trees damaged by the 
balsam woolly aphid. For. Chron. 52:143-144. 

Schroeder, M. J., and C. C. Buck. 1970. Fire weather. Agric. Handb. 360, 
USDA Forest Service. 229 p. 

Skelly, J. M., S. F. Duchelle, and L. W. Kress. 1979. Impact of 
photochemical oxidant air pollution on eastern white pine in the 
Shenandoah, Blue Ridge Parkway, and Great Smoky Mountains National Parks. 
Proc. 2nd Conf. on Sci. Res. in National Parks, San Francisco, CA. 

Smith, F. H. 1967. Effects of balsam woolly aphid infestation on cambial 
activity in Abies grandis . Am. J. Bot. 54:1215-1223. 

Speers, C. F. 1958. The balsam woolly aphid in the Southeast. J. For. 56: 
515-516. 

Varty, I. W. 1956. Adelges insects of silver firs. Gr. Brit. For. Comm. 
Bull. No. 26, London. 75 p. 

Ward, J. D., E. T. Wilson, and W. M. McDonnell. 1973. Status of the balsam 
woolly aphid, Adelges piceae (Ratz.), in the Southern Appalachians - 1972. 
USFS, SA, S & PF, Div. FPM, Asheville, NC. Rep. No. 73-1-35. 



50 



UNDERSTORY CHANGES IN SPRUCE-FIR 
DURING THE FIRST 16-20 YEARS FOLLOWING THE DEATH OF FIR 

H. R. DeSelm and R. R. Boner' 



Abstract. One hundred four 0.04 ha plots were used to sample changes in the 
vegetation following the death of Fraser fir in the Great Smoky Mountains and 
Black Mountains of North Carolina and Tennessee. Fir death had been caused 
by balsam woolly aphid infestation. Vegetation changes in the greatest (16-20 
year) time class in the Black Mountains provides hypotheses which can be tested 
in the Great Smokies where fir death is now occurring. The following mostly 
short-term increases in density or cover have been seen: spruce and yellow 
birch trees, fir, mountain maple and mountain ash saplings, fir, Menziesia, fire 
cherry, round leaf gooseberry, Rubus canadensis, R. idaeus var. canadensis, red 
berried elder subsapling-shrub stems, and ground cover such as certain ferns and 
mosses. 

Additional keywords: Aphid, balsam woolly aphid, Smoky Mountains, Black 
Mountains, succession. 

INTRODUCTION 

It is the purpose of this paper to describe the changes in floristic composition and 
structure of the spruce-fir ( Pi ceo rubens Sarg. - Abies Fraser i (Pursh) Poir.) forests 
following the death of fir after infestation of the balsam woolly aphid ( Adelges piceae 
Ratz.) These changes were advanced to the 16-20 year stage when the field work was 
done. The early stages are to be found now in the central Great Smoky Mountains 
where predictions made here from trends found in the eastern Smokies and Black 
Mountains may be tested. 

Fraser fir is a codominant with red spruce in the high forests of southwestern 
Virginia, East Tennessee, western North Carolina (Little 1975, Pittillo and Smothers 
1979, Shields 1962). Above about 1830 m, and in the Great Smoky Mountains above 
about 1890 m (occasionally lower, Cooley 1954) it is the sole forest overstory dominant 
(Whittaker 1956). These forests have been called a southern phase (Pittillo and Smothers 
1979, Oosting and Billings 1951) of the boreal forest system, but the occurrence of 
many Southern Appalachian endemics (Harper 1947, 1948, White 1982, DeSelm and Clark 
1983), of which some occur in the spruce-fir zone, suggests a period of relative 
geographic isolation from the main system. The vegetation and environment of the 
main boreal system has been reviewed by Larsen (1980, 1982). 



—' Professor, Botany Department and Graduate Program in Ecology, The University of 
Tennessee, Knoxville; The Nature Conservancy, Minneapolis, Minnesota, formerly of the 
Graduate Program in Ecology. The writers acknowledge the support of the Graduate 
Program in Ecology and permission for study from the National Park Service, the U.S. 
Forest Service, and the North Carolina Department of Parks. 



The balsam woolly aphid was introduced into New England and eastern Canada 
from Europe about 1900 (Balch 1952). It was seen on Mt. Mitchell in the Black 
Mountains of western North Carolina at least by 1957 (Speers 1958) and was present 
earlier (Eagar 1978). It was found on Mt. Sterling in the Great Smoky Mountains in 
1963 (Ciesla et al. 1965, Amman 1966) and has been expanding its range southwest in 
the Smokies since that time. The infestation is now nearly complete (personal 
communication, C.C. Eagar, July, 1983). The larger trees are first and most severely 
infected (Johnson 1977, Eagar 1978). 

THE STUDY AREAS 

Physical Environment 

The Great Smoky Mountains (centering 83 30' west longitude, 35 35' north latitude) 
and the Black Mountains (centering at 82 15' west longitude, 35 45' north latitude) are 
the study areas. The Smokies contain nearly 50 km2 of land area over 1675 m elevation 
and the Blacks nearly 25 krcr- of such land - most of this land is spruce-fir or fir 
dominated (Ramseur I960). The Smokies are in Blount, Sevier, and Cocke Counties, 
Tennessee, and Swain and Mitchell counties, North Carolina. The Blacks are in Yancey, 
Buncombe, and M c Dowell Counties, North Carolina. Both ranges lie within the Blue 
Ridge physiographic province (Fenneman 1938) 

The climate of the high elevations of these areas is characterized by high 
precipitation: 238.9 cm (Shanks 1954a, five year study, Great Smokies), and 180.8 cm 
(Carney 1955, Blacks). Precipitation is well distributed monthly but intense storms in 
the zones below and above 1220 m vary from 56 to 194 in a 30 year period (Bogucki 
1972). Temperatures decline upslope but snowfall does not persist over the whole 
winter (Shanks 1954a). 

Bedrocks of the Blacks are Precambrian metamorphics, gneiss and schist, with 
fine granitoid layers. The high Smokies are underlain by the Thunderhead Sandstone 
and the Anakeesta Formation which contains dark, silty to argillaceous rocks altered 
to slate, phyllite and schist (King, Newman and Hadley 1968). Slopes of 20 to 60 
percent are common but some flat areas occur on benches and crests. Soils on course 
textured parent material and a stable surface may be expected to be spodosols, on 
medium textured parent material or unstable substrate mainly umbrepts, and under 
heath vegetation spodosols or histosols (Springer and DeSelm 1983). They are usually 
stoney, acid, shallow and infertile. 

The surface organic layer (0-layer), in one study, weighed 97,975 kg/ha and was 
over 14 X as heavy as the 0-layer from the northern hardwood (beech gap) forest 
adjacent (MCGinnis 1958). 

Flora and vegetation 

Ramseur (I960) found 391 vascular plant taxa in the high elevation communities 
and 145 taxa (37 percent) in the spruce-fir of the 10 high mountain areas examined. 
There were 112 taxa in the Smokies and 55 in the Blacks - more intensive sampling 
will doubtless count more. Interesting floristic elements, as northern taxa occur 
(Ramseur I960, Cain 1930), as do endemics (White 1982) and species of national 
significance because of their rarity (White 1982). Most of these special taxa occur in 
the understory. 



52 



The vegetation of the high Southern Appalachian Mountains was examined from 
a floristc, ecological, forest crop useage, and land use standpoints by the scientists of 
the turn of the last century. These observers include Gattinger (1901), Kearney (1897), 
Harshberger (1903), Ayres and Ashe (1902, 1905) and Pinchot and Ashe (1897). The 
relative inaccessability of the peaks made scientfic study difficult but characterization 
of the flora and its elements got underway (Gattinger, Kearney, Harshberger). Forests 
were characterized and the effects of their destruction on soil erosion and downstream 
flooding were well documented (Pinchot and Ashe, Ayres and Ashe). 

Between 1897 (Pinchot and Ashe) and 1935 (Cain 1935) the relative value of the 
high conifer forests changed dramatically. Pinchot and Ashe state, "Commercially then 
forests are at present unimportant". In contrast, Cain cites the details of potential 
log numbers from trees in the Smokies (Champion Fibre Company data from Mt. 
Mingus). "From the cruise sheets I have found that approximately 50 percent of the 
trees of 18-22 inch d.b.h. contain four 16 foot logs; of the trees from 24-30 inch d.b.h. 
approximately 50 percent contain five 16 foot logs; of the trees 32-36 inch d.b.h. 
approximately 50 percent contain six 16 foot logs while about three percent would cut 
seven logs." Here is an obvious expression of commercial value. Harshberger (1903) 
noted in his community ecology comments, non-forest areas, meadows, grassy balds, 
heath slicks, forest understory "associations" including ones dominated by shrubs, herbs 
and cryptogams, and forest overstory "black" spruce, Fraser fir and their associates. 

The second period of study of this vegetation was initiated by Core (1929) on 
Spruce Knob, West Virginia, Davis (1930) in the Black Mountains, and Cain (1935) in 
the Great Smokies. These and subsequent papers now total in number over 52 (De Young 
et al. 1982). Cain's paper is instructive as he departs from the spruce-fir forest type 
as seen by Harshberger (1903) and Davis (1930) and describes the spruce and fir types 
separately (see also Ashe 1922, who lists red spruce and southern balsam types, and 
red spruce with yellow birch and red spruce and hemlock intergradient types; see also 
Hawley (1932) who describes Southern Appalachian red spruce, red spruce-southern 
balsam fir and yellow birch-red spruce). 

Noted by Cain (1935) in the red spruce type are cover percentages of the six 
strata, their floristic composition and tree basal area (76 mVha). Noted in particular 
is the dominance of large (girth and height) spruce. Cain notes in the southern bqlsam 
fir (Fraser fir) type the much lower heights, the lower basal area (66.15-66.99 mvha) 
and great cryptogram cover throughout the community. He notes the increased 
importance of fir upslope - his fir sample stand comes from 1920 m on Mt. LeConte. 

Oosting and Billings (1951) sought to sample mixed stands mostly in the middle 
elevations, often present data one stand at a time and may show absolute and relative 
data. The Smoky Mountain stands averaged 60.2 m^/ha and varied continuously from 
mostly spruce to mostly fir. The great tree numbers differential is evident in the 
5:12, spruce: fir, total stem ratio (1000 m^ sample) (compare this to the basal area 
ratio 34:2 1). Seedling densities of spruce and fir exceed stems over 2.5 cm d.b.h. by 
78X. The seedling spruce to fir ratio was 1:4.1 Among the individual stands, diameters 
extend to the 34-36 inch (86-9 1 cm) class in spruce and 32-34 (81-86 cm) class in fir 
but distributions of two inch classes do not fall on a typical inverse J-curve in an 
arithmatic plot as would be expected (Whipple and Dix 1979) among tolerant taxa 
(Daniel et al. 1979). It would be instructive to determine the model followed by their 



53 



data (Schmalzer 1982). Gaps in diameter sizes in individual stands may represent cyclic 
reproduction and/or cyclic e. g. blowdown. 

Tree growth was also investigated by Oosting and Billings (1951). Spruce to 359 
years was found but large spruce were commonly 200-250 years; their plotted relation 
suggests about 19 inches (48.3 cm) in 200 years. The smaller and younger-at-maturity 
firs averaged about 12 in (30.5 cm) in 100 years. 

Shanks (1954b) resampled the Mt. Mingus spruce-fir stands seen by Cain and 
Oosting and Billings and reported basal areas for trees over 4 inches (10 cm) d.b.h. : 
Cain 329.2 square feet (90.0 m^/ha), Oosting and Billings 242.6 square feet (55.7 m^/ha) 
and his own study 218.5 square feet (50.2 m^/ha), 293.7 square feet (67.4 m^/ha), 293.5 
square feet (67.4 m^/ha), and 203.5 square feet (46.7 m^/ha). Other basal areas reported 
are 34.4-65.6 mVha ' n spruce-fir and 29.1-66.1 m^/ha in fir in the Balsam Mountains 
(Weaver 1972). Golden (1974) reports 48.1 m^/ha in the Smokies spruce-birch. Boner 
(1979) reports 161.2-232.0 square feet/acre (37.0-53.3 m^/ha) in Smokies spruce-fir. 
Crandall (1958) reports 120-232 square feet/acre (27.6-53.3 m^) in the fir forests, 120- 
361 square feet/acre (27.6-82.9 m^/ha) in spruce-fir stands, 168-368 square feet/acre 
(38.6-84.5 m2/ha) in spruce types and 120-248 square feet/acre (27.6-56.9 m^/ha) acre 
in the spruce - hardwood types in the Smokies. 

The complexity of the understory has long been of interest. While the possibility 
of productivity - based site types remains (cf. Heimburger 1934), understory types were 
topographically based (Whittaker 1956) with five (valley to ridge) in the spruce, and 
four (north slope to ridge) in fir stands. This was refined by Crandall (1958) into four 
fir types, seven types in the spruce and spruce - fir (three also occur in the fir) and 
three types in the spruce-hardwood (one also occurs in the spruce-fir and fir forests). 
The prevalence here of cryptograms is notable in this Appalachian vegetation. 

Spruce-fir vegetation biomass is heavily concentrated in the overstory tree stratum 
and amounts to 110-245 metric tons/ha in the Balsams(Weaver and DeSelm 1973), 351 
tons/ha (Shanks, Clebsch and DeSelm 1961) or 300-340 tons/ha in the Smokies (Whittaker 
1966) and 200-210 tons/ha in the Smokies fir forests (Whittaker 1966). Productivity in 
the spruce-fir ranges from 580 g/m^/year (Shanks, Clebsch and DeSelm 1961) to 944- 
1402 g/nrr/year in the Smokies fir forests (Whittaker 1966); and 816 g/m^/year in young 
Balsam Mountain spruce-fir (Weaver 1972). Nutrient cycling studies were initiated in 
the Smokies (Shanks, Clebsch and DeSelm 1961) and in the Balsams (Weaver 1972) and 
the current acid rain problem points up the need for continued and extended studies. 
This third, functional, aspect of this ecosystem was initiated by Shanks, Clebsch and 
DeSelm (1961), and Whittaker (1961). 

METHODS 

During the summer of 1974, 104 0.04 ha circular plots (99 plots are reported 
here) were placed in spruce-fir vegetation in the Great Smoky Mountains National Park 
and Mt. Mitchell State Park and adjacent Pisgah National Forest. Sampled stands were 
located using personal reconnaisance, personal communications with appropriate people 
and information in Speers 1958, Nagel 1959, Ciesla et al. 1965, Aldrich and Drooz 1967, 



54 



and Rauschenberger and Lambert 1968, 1969, and 1970. Proposed stands were located 
on topographic maps so that areas of similar topography between 1560 m and 2010 m 
could be chosen. Stands were chosen to represent vegetation not modified by balsam 
woolly aphid attack (Central Smokies) and vegetation with fir dead as long and 20 years 
(eastern Smokies, Mt. Mitchell, Pisgah National Forests). Although other perturbations 
were minimized in the stands, plot locations in stands were otherwise random. 

Plot diameter was corrected for slope angle (Bryan 1956). All stems greater 
than 2.5 cm d.b.h. were tallied by species. Stems 2.5 - 12.4 cm (saplings) were counted 
by species. Stems 12.5 cm and greater (overstory) were counted by species in five cm 
d.b.h. classes. Two subplots 1.8 m wide were established across the diameter of the 
plot-totaling 0.008 ha - herein all stems 0.6 m tall to 2.5 cm d.b.h. (subsaplings - shrubs) 
were counted by species. Also eight subplots 0.3 m x 3.3 m (totaling 0.0008) (ha) were 
established wherein cover of each taxon less than 0.6 m tall was estimated. Other 
plot data collected were elevation, slope angle, local slope position, slope form (flat, 
convex, concave), aspect, surface rock exposed, canopy closure, condition of overstory 
fir, and probable date of fir death from growth rings. Data were calculated per plot 
as absolute density, absolute basal area or relative cover (percent). Plots were grouped 
by elevation and time since opening of the canopy. 

Vascular plant nomenclature follows Radford et al. (1968); that for 
bryophytes follows Crum et al. (1973). 

RESULTS 

Overstory taxa have responded during time in more than one way (Table I). Fir 
( Abies) , more abundant above 1800 m, has declined (d) greatly in the affected plot 
groups but by I 1-20 years has recruited saplings into the overstory class. The densities 
of Acer, Amelanchier , Betula lenta, and Prunus have scarcely changed (h) but are 
present in only certain time classes. The excluded Fagus (e) is special, but all of these 
have too low densities to conclude that the openings have a profound effect. The 
densities of Betula lutea and Sorbus, although not present in each age class, seem to 
be increasing (h-p). Picea is holding its own except at 11-20 years which has declining 
densities (h-d). Similar behavior appears in the basal areas of the same plots (Table II). 

As is usually seen in such data, more taxa occur in the sapling than overstory 
layers (Table III). Although numbers are low and each time set is confounded with 
geographic location there are several kinds of reaction to the openings. Acer 
pensylvanicum, Ilex, Sambucus and Tsuga have invaded the openings (i) and Betula lenta 
and Viburnum cassinoides have been excluded from the openings (e). Several taxa with 
low densities throughout peak in the openings, Acer spicatum, Amelanchier , Viburnum 
alnifolium at 5-6 years, and Sorbus and Prunus at 11-15 years (h-p). Betula lutea , 
Picea and Rhododendron peak in the 5-10 year period (h-p). Beyond 10 years, fir 
sapling density increases; by 11-15 years the stem numbers equal those in undisturbed 
areas (h-p). 

Numbers of subsapling-shrub taxa are 26 (Table IV) compared to 15 sapling taxon 
previously seen. Fir numbers suffer a temporary decline (5-10 years) but by I 1-20 years 
in the Black Mountains the numbers exceed the pre-infestation levels (of the Smokies). 
Subsaplings of taxa maintaining this density (h) but with low frequency are Acer 
pensylvanicum, Amelanchier , and Rhododendron sp. Ribes qlandulosum, Rubus idaeus 



55 



Table L— Overstory density of disturbed and undisturbed stands (stem/ha.) 











Years Since Openi 


ng of Canopy 




Taxa 


Oa 


0b 


5-6 c 


7-IO d 


Il-I5 e 


l6-20 f 


Abies fraseri (d) 


66.2 


113.3 


1.2 




22.9 


13.4 


Acer spicatum (h) 


0.6 




0.6 


0.9 


0.4 




Amelanchier arbor ea 














var. laevis (h) 


0.8 






0.6 






Betula lenta (h) 


3.3 






0.7 






Betula lutea (h-p) 


6.8 


0.8 


5.8 


17.1 






Fagus grand if olia (e) 


0.9 


0.2 










Picea rubens (h-d) 


33.0 


26.4 


24.3 


30.9 


10.4 


6.6 


Prunus pensylvanica (h) 


0.6 




0.6 




0.9 




Sorbus americana (h-p) 


1.3 


2.8 


2.3 




6.8 


4.1 


Total 


113.5 


143.7 


34.8 


50.2 


41.4 


24.1 





5/ 27 plots, Smokies, undisturbed, <6000 feet (<I829 m) elevation. 

°J 19 plots, Smokies, undisturbed ^6000 feet (>I829 m) elevation. 

£/ 8 plots, Black Mts. 5500-6000 feet (1676-1829 m) elevation, 

d/ 22 plots, Mt. Sterling, Smokies, <6000 feet ( < 1829 m). 

y 10 plots, Black Mts., <6000 feet ( < 1829 m) elevation. 

1/ 13 plots, Black Mts, >6000 feet (> 1829 m) elevation. 



56 



Table II.— Overstory basal area of disturbed and undisturbed stands (sq. m./ho) 



Years Since Opening of Canopy*!/ 
Taxa 5-6 7-10 11-15- 16-20 



Abies fraseri (d) 19.4 32.1 0.1 8.9 4.8 

Acer spicatum (h) 
Amelanchier arbor ea 

var. laevis (h) 
Betula lenta (h) 
Betula lutea (h-p) 
Fagus grandifolia (e) 

Picea rubens (h-d) 13.8 26.9 17.4 5.8 2.4 

Prunus pensylvanica (h) 
Sorbus americana (h-p) 0.2 0.5 0.3 0.9 0.6 

Total 53.2 47.2 33.8 28.7 15.8 7.8 



19.4 


32.1 


0.1 




8.9 


0.1 




0.1 


0.2 


0.1 


0.3 






0.1 




2.8 






1.3 




2.9 


0.6 


6.1 


9.7 




0.3 


0.2 








27.1 


13.8 


26.9 


17.4 


5.8 


0.1 




0.3 




0.1 


0.2 


0.5 


0.3 




0.9 



9_'plot distribution as in Table I. 



57 



Table 111. — Sapling density of disturbed and undisturbed stands (stems/ha) 

Years Since Opening of Canopy 
Taxa 5-6 7-10 il-15 16-20 



Abies fraseri (h-p) 46.0 37.5 3.5 10.3 42.7 23.7 

Acer pensylvanicum (i) 0.6 

Acer spicatum (h-p) 3.4 I 1.6 1.7 1.3 

Amelanchier arbor ea 

var. laevis (h-p) 
Betula lenta (e) 
Betula lutea (h-p) 
Ilex ambigua var. 

montana (i) 
Picea rubens (h-p) 1.9 5.5 9.3 18.8 5.8 4.4 

Prunus pensylvanica (h-p) 
Rhododendron catawbiense 

(h-p) 
Sambucus pubens (i) 

Sorbus americana (h-p) 0.3 3.4 2.9 0.2 22.5 5.9 

Tsuga canadensis (i) 
Viburnum alnifolium (h-p) 1.2 2.3 

Viburnum cassinoides (e) 0.2 

Total 68.4 48.5 41.2 54.7 81.3 34.0 



0.2 
i i 




3.5 


0.2 




i . i 
3.6 


1.9 


5.2 
2.3 


7.2 
1.7 


3.2 


11.9 


5.5 


9.3 


18.8 


5.8 


0.2 


0.2 




0.2 


4.5 


0.3 






13.1 
0.9 


1.3 


0.3 


3.4 


2.9 


0.2 
0.4 


22.5 



^/plot distribution as in Table I, 



58 



Table IV.— Subsapling-shrub density in disturbed and undisturbed stands (stems/ha) 



175.8 


225.8 


17.4 


133.3 


359.8 


5.3 




2.8 


3.6 




15.0 




92.5 


29.3 


6.8 


3.8 




2.8 






17.2 










18.7 


I.I 


28.9 
2.8 


19.2 


2.2 



Years Since Opening of Canopy^/ 
Taxa 5-6 7-10 11-15 16-20 



Abies fraseri (h-p) 275.8 225.8 17.4 133.3 359.8 474.7 

Acer pensylvanicum (h) 
Acer spicatum (h-p) 
Amelanchier arborea 

var. laevis (h) 
Betula lenta (e) 
Betula lutea (h-p) 
Cornus alternifolia (i) 
Diervilla sessilifolia (e) 3.2 

Fagus grandifolia (e) 0.8 

Hydrangea arborescens (i) 8.7 

Ilex ambigua var. 

montana (h-p) 
Menziesia pilosa (i) 
Picea rubens (h) 
Prunus pensylvanica (i) 
Rhododendron 

catawbiense (h) 
Rhododendron maximum 

(i) 
Rhododendron sp. (i) 
Ribes glandulosum (i) 
Ribes rotundifolium (h-p) 
Rubus canadensis (h-p) 
Rubus idaeus var. 

canadensis (i) 
Sambucus pubens (h-p) 
Sorbus americana (h-p) 
Tsuga canadensis (i) 
Vaccinium erythrocarpum 

(h-p) 
Viburnum alnifolium 

Total 



3.8 
86.2 


10.6 


2.8 
5.9 
17.4 


5.5 

44.0 
27.5 


8.9 
6.8 


59.1 

17.2 

1.6 


2.3 


I.I 




1.0 






151.4 


2.1 
2.1 


5.9 
404.7 


1.0 

1.8 
477.3 


6.8 
1202.8 


6.3 

9.3 

35.8 

364.2 


3.0 
12.0 


13.8 
8.5 


14.4 
5.9 


456.2 

32.2 

1.0 


384.5 
72.0 
42.5 


1316.9 
90.2 
124.5 


175.4 
574.0 


76.7 
104.4 


338.1 
647.5 


103.0 
27.5 


11.3 
4.5 


7.7 
17.2 


1144.7 


449.4 


1598.5 


1363.7 


2108.9 


2524.7 



—'plot distribution as in Table I. 



59 



Table V.— Percent cover of ground cover taxa of disturbed and undisturbed stands 

Years Since Opening of CanopyQ-' 
Taxa 5-6 7-10 11-15 16-20 



Abies fraseri (h) 
Acer spicatum (e) 
Agrostis stolonifera (h) 
Angelica sp. (i) 
Arisaema triphyllum (h) 
Aster acuminatus (h-p) 
Aster divaricatus (h-p) 
Athyrium asplenioides 

(h-p) 
Atrichum undulatum (i) 
Betula lenta (e) 
Brotherella recur vans 

(h-p) 
Carex aestivalis (i) 
Carex brunnescens (h) 
Carex debilis var. 

rudgei 
Carex intumescens (h-p) 
Che I one lyonii (h-p) 
Cimicifuga racemosa (h) 
Circaea alpina (h-p) 
Clintonia boreal is (h-p) 
Dennstaedtia puncti- 

lobula (h) 
Dicranodontium 
denudatum (h) 
Dicranum fuscescens (h) 
Dryopteris intermedia 

(h-p) 
Epifagus virginiana (e) 
Eupatorium rugosum (h) 
Glyceria striata (e) 
Houstonia serpyllifolia (h) 
Hylocomium splendens (h) 
Impatiens pallida (h) 
Laportea canadensis (e) 
Liverworts (h) 
Luzula sp. (h) 



0.2 


0.3 


0.3 


0.5 


0.7 




0.1 












0.03 


0.01 






0.1 
0.04 


0.4 
0.1 


0.04 


0.01 




0.1 


0.4 




1.0 


4.5 


6.1 


16.0 


11.3 


20.6 


0.1 


0.02 






I.I 


2.9 


13.6 


25.6 


5.4 


3.2 


38.7 
1.0 


13.1 


0.004 












11.7 


3.0 


18.6 


6.8 


1.9 


4.5 
0.1 


0.02 


0.7 


0.1 


0.3 


0.03 


0.1 


0.03 




0.01 




0.1 


0.3 


0.004 


0.02 




0.01 


1.6 


0.02 


0.1 


0.4 
0.1 






4.7 
0.03 


19.7 


0.004 




0.1 


1.2 






1.7 


1.6 


2.6 


0.5 


0.8 


1.7 


0.3 






0.3 






0.5 


0.3 


0.9 


0.7 


0.5 


0.3 


0.2 


0.5 


0.01 


0.1 






15.6 


12.7 


15.5 


29.3 


13.0 


7.6 


0.004 












0.03 






0.1 




0.2 


0.01 












0.02 






0.02 


0.04 




11.5 


10.4 


8.6 


11.3 


7.3 


I.I 


0.1 


0.9 


0.6 




1.0 


0.8 


0.3 


0.1 










2.5 


2.4 


I.I 


0.4 


0.2 


0.3 




0.01 




0.03 


0.6 





60 



Table V.— (Continued) 



Years Since Opening CanopyE' 
Taxa a D 5-6 7-10 11-15 16-20 



Lycopodium lucidulum 










(h) 


2.7 




0.1 


0.1 


Medeola virginiana (e) 


0.01 








Monotropa uniflora (e) 




0.01 






Oxalis acetosella (h) 


33.8 


29.0 


39.0 


27.9 


Picea rubens (h) 


0.04 




0.3 


0.04 


Polygonum cilinode (i) 








4.7 


Polypodium virginianum 










(i) 






0.04 




Polytrichum ohioense (h) 


0.5 


1.6 




0.01 


Ptillium cristacastrensis 










(e) 




0.3 






Rhytidiadelphus triquetrus 


(h) 




0.2 




Rubus canadensis (h) 


0.1 


0.01 




0.2 


Sambucus pubens (h) 


0.02 






0.1 


Saxifraga michauxii (h) 




0.1 






Senecio rugelia (h) 


8.2 


12.5 




4.2 


Smilacina racemosa (e) 




0.01 






Solidago glomerata (h-p) 


0.5 


0.8 






Sorbus americana (e) 


0.03 


0.04 






Sphagnum subnitens 










(h) 


1.2 


1.2 


2.1 


1.5 


Stachys clingmanii (e) 




0.2 






Trilliumm erectum (h) 


0.01 






0.01 


Vaccinium erythrocarpum 










(e) 


0.3 


0.1 






Veratrum viride (i) 










Viburnum alnifolium (i) 






0.02 




Viola sp. (h) 


0.01 






0.01 



7.5 4.5 

0.4 0.1 
0.01 

0.05 0.1 0.02 

1.2 

9.2 13.7 

1.0 3.2 



0.1 0.2 

0.01 0.01 

Total 107.1 109.7 101.5 104.9 103.5 96.7 



^Plot distribution as in Table I. 



61 



var. canadensis and Tsuga. Certain taxa occur in both kinds of stands but their density 
peaks in the disturbance - some dramatically so (h-p). Taxa which peak in the first 
10 years are Acer spicatum, Betula jutea, Ilex, Sambucus , Vaccinium and Viburnum; 
those peaking at I 1-20 years are Rubus canadensis, Sorbus, and Ribes rotundifolium. 

Among the ground cover taxa (Table V) the same categories occur. Fir is 
maintaining its seedling populations in the disturbed area except at 16-20 years-it is 
not known whether this is a significant loss. A total of 27 are maintaining their 
populations (h), with variable frequency and cover in the disturbed plots. These include 
six bryophytes, two tree, two shrub, and 17 herb taxa. Twelve taxa occur in the 
undisturbed plots but are excluded (e) or have not yet invaded the disturbed areas; 
these include small trees, a shrub, several herb taxa and a bryophyte. Ground cover 
invaders (i) not seen in the undisturbed areas include seven taxa: the shrub Viburnum, 
the bryophyte Atrichum, and several herbs. Ground cover taxa which occur in both 
kinds of areas but whose cover peaks (h-p) in the distrubed areas number 10, including 
a bryophyte and nine herb taxa. The cover of the bryophyte taxa peaked early in the 
20 year period of change, the two ferns Athyrium and Dryopteris and two herbs Carex 
intumescens and Circaea peaked in the middle (7-15 years) and the other taxa Solidago, 
Aster, and Che I one peaked in the I 1-20 year period. 

DISCUSSION 

The underlying assumption of this study that this vegetation is uniform enough 
to find sampling sites varying only in the time of fir death must be modified to include 
the variables of unknown past history as consequences of vertical zonal shifts during 
the hypsithermal period (Billings and Mark 1957), and logging in the Black Mountains 
and the Smokies Mt. Sterling area (Saunders 1979) although they were not in plot 
locations of this study. Other variables include the gradient spruce/fir importance 
change through the spruce-fir zone and the distinctive understory types which Whittaker 
(1956) related to topographic position. All of these may result in variations in abundance, 
shown here qs presence, density, basal area and cover in a time class. Other factors 
acting through past history include population genetic makeup shifts in competitors, 
and changes in past disease and insect predation. 

The recovery of Abies from the initial attack of the aphid as evidenced by new 
overstory stems and partial recovery of sapling stems, the great rise in numbers of 
subsapling stems strongly suggests the possibility of recovery. However, the paucity 
of seedlings negates this. At the time of this study these small diameter fir were not 
being killed. 

The invader taxa, not present in the central Smokies undisturbed plots, may 
indeed be taxa whose propogule mobility allows them to invade open areas - or they 
may be low frequency overlooked taxa. They include two with winged fruit, seven 
with pulpy, berry- 1 ike fruit, one hooked fruit and taxa two spore-borne. Others are tiny 
to moderate-sized seed or fruit whose dispersal mechanism is less obvious. Two of 
these taxa ocurred in the seed rain of a spruce and adjacent beech forest ( Angelica 
and Viburnum alnifolium) in the Smokies (Pavlovic 1981). In addition, Prunus 
pensylvanicum and Sambucus pubens occurred in the spruce stand soil seed bank. While 
these data are suggestive, that most of the woody taxa are know to at least occur to 
high elevation ( > ca. 1980 m, Stupka, 1964) they indicate that they simply may have 
too low frequency to have been seen in the undisturbed plots, and their occurrence in 
disturbed plots places them in the invader class. 

62 



The excluded class includes taxa of the undisturbed which do not occur in the 
disturbed areas. Only two of 14 occur in Pavlovic's (1981) seed rain or spruce stand 
seed bank ( Fagus and Laportea, respectively). The persistance of Fagus and Betula 
lenta in the disturbed areas, mostly above 1830 m, is limited by the apparent low 
tolerance of the taxa to elevation extremes (Stupka 1964). It seems possible that the 
low frequency problem may be affecting the apparent behavior of other taxa. 

Most of the taxa of tables l-V area at least maintaining their density or 
cover through time. Those with particularly low densisty or cover drop in and out of 
adjacent time classes (see Acer spicatum Table I, Viburnum alnifolium Table III, Acer 
pensylvanicum Table IV and Agrostis Table V). Some exhibit what seems to be significant 
density or cover peaks in the disturbed plots. While the Southern Appalachian spruce- 
fir has not been shown to exhibit wave destruction (Reiners and Lang 1979), patchwork 
regeneration following windthrow (Cooper 1913) or even a long term natural disturbance 
cycle (Lorimer 1 977), enough types of natural distrubances are in evidence in these 
forests (i. e. windthrow, ice storms, insects, debris slides) that it would be a surprise 
to find the native taxa not positively or negatively adapted to such prevalent changes. 
These taxa are virutally all perennials but studies of the autecology of the shrubs, 
herbs and bryophytes are unknown. Such studies would answer many of the questions 
raised by increased or decreased density or cover, with disturbance, of the understory. 
The considerable increase in the density of several shrubs raises the possibility of their 
interference with overstory regeneration and survival of herbaceous taxa. Several taxa 
are in the sampling category: excluded from disturbed areas. Their continued success 
in these forests should be examined. 

CONCLUSIONS 



The differences in concepts of types and their intergrades in the literature 
suggests that not all types are fully known and not all ecotonal types are described. 
For example, although spruce-birch is well known, spruce-hemlock and spruce-oak are 
not well known. 

The degree to which our spruce-fir is cyclic is still little understood. The model 
followed by size or age-class data is unknown. 

The relationship of understory type to understory or overstory production is not 
settled. Probable cyclic reproduction and survival of the overstory and the death of 
fir makes this difficult to assess now. 

Production and nutrient cycling studies need reemphasis in the face of a changing 
atmospheric environment. 

The decimation of overstory fir and its decreased density and basal area is 
accompanied by differential behavior of other plot tree taxa, some are maintaining 
their importance, some are losing, and some are gaining in importance. 

Sapling and subsap ling-shrub size plants may invade, be excluded from, may 
maintain their approximate numbers, or increase in density or cover on the disturbed 
plots. Density of Ribes rotundifolium, Rubus canadensis, Rubus idaeus var. canadensis, 
Sambucus , Vaccinium erythrocarpum, and Viburnum alnifolium exhibit markedly high 
densities in at least one set of years since opening of the canopy. 

63 



Looking at taxa excluded (e) from the disturbed areas, Betula lenta occurs in 
undisturbed overstory, sapling and ground cover plots but in disturbed plots it is only 
in the overstory. Viburnum cassinoides occurs in undisturbed sapling plots but in no 
other smaller size classes anywhere. Diervilla occurs in subsap ling-shrub undisturbed 
plots but in no other smaller size classes. Fagus occurs in undisturbed tree and 
subsapling plots but in no disturbed plots nor ground cover (reproduction) plots. Of 
course the parasite Epifagus follows Fagus exactly. Glyceric , Laportea, Medeola, 
Monotropa, Smi lacing and Stachys are herbs which occur in undisturbed but not disturbed 
plots. It seems that these are the taxa being negatively affected by fir death. Their 
continued importance in these forests should be examined. 



64 



LITERATURE CITED 

Aldrich, R. C. and A. T. Drooz. 1967. Estimated Fraser fir mortality and balsam 
woolly aphid infestation trend using aerial color photography. Forest Sci. 13: 
300-313. 

Amman, G. D. 1966. Some new infestations of the balsam woolly aphid in North 
Carolina with, possible modes of dispersal. Jo. Econ. Ent. 59: 508-511. 

Ashe, W. W. 1922 Forest types of the Appalachians and White Mountains. 
Elisha Mitchell Sci. Soc. Jo. 37: 183-198. 

Ayres, H. B. and W. W. Ashe. 1902. Forests and forest conditions in the Southern 
Appalachians, pp 45-109. In: Message from the President of the United States 
transmitting a report of the Secretary of Agriculture in relation to the forests, 
rivers, and mountains of the Southern Appalachian region. Government Printing 
Office, Washington, D. C. 210 pp. 

Ayres, H. B. and W. W. Ashe. 1905. The southern Appalachian forests, U. S. G. S. 
Prof. Paper 37: 1-291. 

Balch, R. E. 1952. Studies of the balsam woolly aphid, Adelges piceae (Ratz.), and 
its effects on balsam fir, Abies balsamea (L.) Mill. Can. Dept. Agric. Publ. 867. 

Billings, W. D. and A. F. Mark. 1957. Factors involved in the persistence of montane 
treeless balds. Ecology 38: 140-142. 

Bogucki, D. J. 1972. Intense rainfall in Great Smoky Mountains National Park. 
J. Tenn. Acad. Sci. 47: 93-97. 

Boner, R. R. 1979. Effects of Fraser Fir death on population dynamics in Southern 
Appalachian boreal ecosystems. M. S Thesis. University of Tennessee, Knoxville. 
105 pp. 

Bryan, M. B. 1956. A simplified method of correcting for slope on circular sample 
plots. J. Forestry 54: 442-445. 

Cain, S. A. 1930. Certain floristic affinities of the trees and shrubs of the Great 
Smoky Mountains and vicinity. Butler Univ. Bot. Stud. I: 129-150. 

Cain, S. A. 1935. Ecological studies of the vegetation of the Great Smoky Mountains. 
II. The quadrat method applied to sampling spruce and fir forest types. Amer. 
Midland Nat. 16: 566-584. 

Carney, C B. 1955. Weather and climate in North Carolina. Agric. Expt. Sta. Bull. 
396. North Carolina State College, Raleigh, North Carolina. 

Ciesla, W. M., H. L. Lambert and R. T. Franklin. 1965. Status of the balsam woolly 
aphid in North Carolina and Tennessee— 1 964. U. S. Forest Service Report 
65-1-1. II pp. 

Cooley, E. H. 1954. A study of plant distribution patterns at a mid-altitude 
location in the Great Smoky Mountains National Park. M. S. Thesis. 
Univ. of Tennessee, Knoxville. 56pp. 

65 



Cooper, W. S. 1913. The climax forest of Isle Royal, Lake Superior, and its development. 
Bot. Gaz. 55: 1-44, 115-140, 189-235. 

Core, E. L. 1929. Plant ecology of Spruce Mountain, West Virginia. Ecology 10: 1-13. 

Crandall, D. L. 1958. Ground vegetation patterns of the spruce-fir area of the Great 
Smoky Mountains National Park. Ecol. Monogr. 28: 337-360. 

Crum, H. A. , W. C. Steele, and L. E. Anderson. 1973. A new list of mosses of North 
America north of Mexico. The Bryologist 76: 85-130. 

Daniel, T. W., J. A. Helms, and F. S. Baker. 1979. Principles of silviculture. Second 
Ed. MCGraw-Hill Book Co. New York. 500 pp. 

Davis, J. H. 1930. Vegetation of the Black Mountains of North Carolina: an ecological 
study. Jour. Elisha Mitchell Sci. Soc. 45: 291-318. 

DeSelm, H. R. and G. M. Clark. 1983. Potential National Natural Landmarks of the 
Appalachian Ranges Natural Region of the eastern United States. Draft report to 
the National Park Service C-92 1 1 3(78). Knoxville, Tennessee. 

DeYoung, H. R., P. S. White, and H. R. DeSelm. 1982. Vegetation of the Southern 
Appalachians: an indexed bibliography, 1805-1982. NPS-SER Atlanta, GA 94 pp. 

Eagar, C. C. 1978. Distribution and characteristics of balsam woolly aphid infestations 
in the Great Smoky Mountains. M. S. University of Tennessee, Knoxville. 72 pp. 

Fenneman, N. M. 1938. Physiography of eastern United States. M c Graw-Hill, 
New York. 714 pp. 

Gattinger, A. 1901. The flora of Tennessee and a philosophy of botany. Gospel 
Advocate Pub. Co., Nashville. 296 pp. 

Golden, M. S. 1974. Forest vegetation and site relationships in the central portion of 
the Great Smoky Mountains. Ph.D. Dissertation. University of Tennessee, 
Knoxville. 275 pp. 

Harper, R. M. 1947. Preliminary list of Southern Appalachian endemics. Castanea 
12:100-112. 

Harper, R. M. 1948. More about Southern Appalachian endemics. 13: 124-127. 

Harshberger, J. W. 1903. An ecological study of the flora of mountainous North 
Carolina. Bot. Gaz. 36: 241-258, 368-383. 

Hawley, R. C. 1932. Forest cover types of the eastern United States. Jo. For. 30: 1-48. 

Heimberger, C.C. 1934. Forest-type studies in the Adirondack Region. Cornell Univ. 
Agr. Expt. Sta. Mem. 165: 1-122. 

Johnson, K. D. 1977. Balsam woolly aphid infestations of Fraser Fir in the Great 
Smoky Mountains. M.S. Thesis Univ. of Tennessee, Knoxville, 64 pp. 

66 



Kearney, T. H. Jr. 1897. The pine-barren flora in the eastern Tennessee mountains. 
Plant World I: 33-35. 

King, P. B., R. B. Neuman and J. B. Hadley. 1968. Geology of the Great Smoky 

Mountains National Park, Tennessee and North Carolina. U.S.G.S. Prof. Paper 
587. 

Larsen, J. A. 1980. The boreal ecosystem. Academic Press. New York. 500 pp. 

Larsen, J. A. 1982. Ecology of the northern lowland bogs and conifer forests. Academic 
Press. New York. 307 pp. 

Little, E. L. Jr. 1975. Rare and local conifers in the United States. U. S. Forest 
Service Conservation Research Report No. 19. 

Lorimer, C. G. 1977. The presettlement forest and natural disturbance cycle of 
northeastern Maine. Ecology 58: 139-148. 

McGinnis, J. T. 1958. Forest litter and humus types of east Tennessee. M. S. Thesis. 
University of Tennessee, Knoxville. 82 pp. 

Nagel, W. P. 1959. Status of the balsam woolly aphid in the southeast in 1958— with 
special references to the infestations on Mount Mitchell, North Carolina and 
adjacent lands. U. S. D. A. Forest Service, Southeast Forest Experiment Station 
Report 59-1. 

Oosting, H. J. and W. D. Billings. 1951. A comparison of virgin spruce-fir forest in 
the northern and southern Appalachian system. Ecol. 32: 84-103. 

Pinchot, G. and W. W. Ashe. 1897. Timber trees and forests of North Carolina. 
N. C. Geol. Surv. Bull. No. 6. 

Pavlovic, N. B. 1981. An examination of the seed rain and seed bank for evidence of 
seed exchange between a beech gap and a spruce forest in the Great Smoky 
Mountains. M. S. Thesis. Univ. of Tennessee, Knoxville. 155 pp. 

Pittillo, J. D. and G. A. Smothers. 1979. Phytogeography of the Balsam Mountains 
and Pisgah Ridge, Southern Appalachian Mountains. Veroff. Geobot. Inst. ETH, 
Stiftung Rubel, Zurich. Heft 68: 206-245. 

Radford, A. E., H. E. Ahles, and C. R. Bell. 1968. Manual of the vascular flora of 
the Carolinas. Univ. of North Carolina Press, Chapel Hill. 1183 pp. 

Ramseur, G. S. I960. The vascular flora of high mountain communities of the Southern 
Appalachians. Jour. Elisha Mitchell Sci. Soc. 76: 82-112. 

Rauschenberger, J. L. and H. L. Lambert. 1968. Status of the balsam woolly aphid 
on Mount Mitchell State Park. U. S. D. A. Forest Service Report No. 69-1-27. 

Rauschenberger, J. L. and H. L. Lambert. 1969. Status of the balsam woolly aphid in 
the Southern Appalachians-- 1 968. U. S. D. A. Forest Service Report No. 69-1-29. 

67 



Rauschenberger, J. L. and H. L. Lambert. 1970. Status of the balsam woolly aphid in 
the Southern Appalachians— 1969. U. S. D. A. Forest Service Report No. 70-1-44. 

Reiners, W. A. and G. E. Lang 1979. Vegetational patterns and processes in the balsam 
fir zone, White Mountains, New Hampshire. Ecology 60: 403-417. 

Saunders, P. R. 1979. The vegetational impact of human disturbance on the spruce- 
fir forests of the Southern Appalachian mountains. Ph.D. Diss. Duke University, 
Durham, N. C. 177 pp. 

Schmalzer, P. A. 1982. Vegetation of the Obed Wild and Scenic River, Tennessee, and 
a comparison of reciprocal averaging ordination and binary discriminant analysis. 
Ph.D. Diss., University of Tennessee, Knoxville. 236 pp. 

Shanks, R. E. 1954(a) Climates of the Great Smoky Mountains. Ecology 35: 354-361. 

Shanks, R. E. 1954(b) Plotless sampling trials in Appalachian forest types. Ecology 
35: 237-244. 

Shanks, R. E., E. E. C. Clebsch and H. R. DeSelm. 1961. Estimates of standing crop 
and cycling rate of minerals in Appalachian ecosystems. Unpublished M.S. 
University of Tennessee, Knoxville. 14 pp. 

Shields, A. R. 1962. The isolated spruce and spruce-fir forests of southwestern Virginia. 
Ph.D. Diss. University of Tennessee, Knoxville. 197 pp. 

Speers, C. F. 1958. The balsam woolly aphid in the southeast. J. Forestry 56: 515-516. 

Springer, M. E. and H. R. DeSelm. 1983. Forest soils of the Great Smoky Mountains 
and the Ridges and Valleys. Tour I, Sixth North American Forest Soil Conference. 
Processed report, University of Tennessee, Knoxville. 22 pp. 

Stupka, A. 1964. Trees, shrubs, and woody vines of Great Smoky Mountains National 
Park. University of Tennessee Press. Knoxville. 186 pp. 

Weaver, G. T. 1972. Dry matter and nutrient dynamics in Red spruce-Fraser Fir and 
Yellow Birch ecosystems in the Balsam Mountains, Western North Carolina. Ph.D. 
Diss. University of Tennessee,-Knoxville. 406 pp. 

Weaver, G. T. and H. R. DeSelm 1973. Biomass distributional patterns in adjacent 
coniferous and deciduous forest ecosystems. IUFRO Biomass Studies S4.0I: 
413-427. Vancouver, 20-24 August. 

White, P. S. 1982. The flora of Great Smoky Mountains National Park: an annotated 
checklist of vascular plants and a review of previous floristic work. NPS-SER 
Research/Resources Management Report SER-55. 

Whipple, S. A. and R. L. Dix. 1979. Age structure and successional dynamics of a 
Colorado subalpine forest. Amer. Midi. Nat. 101: 142-158. 



68 



Whittaker, R. H. 1956. Vegetation of the Great Smoky Mountains. Ecol. Mongr. 26: 1-80. 

Whittaker, R. S. 1961. Estimation of net primary production of forest and scrub 
communities. Ecology 42: 177-180. 

Whittaker, R. H. 1966. Forest dimensions and production in the Great Smoky Mountains. 
Ecology kl: 103-121. 



69 



REGIONAL DIFFERENCES OF SPRUCE-FIR FORESTS 
OF THE SOUTHERN BLUE RIDGE SOUTH OF VIRGINIA 



J. Dan Pittillo* 



Abstract. — A summary of the current available information for the 
seven ranges that support spruce-fir forests south of Virginia in 
the high mountains of North Carolina and Tennessee is presented. 
Literature that pertains to the specific sites is supplemented 
with comments on some of the species that are characteristic of 
the given ranges. The isolated nature of the spruce-fir 
communities that occupy the various range peaks and how each site 
has its special set of plant species is discussed. Suggestions for 
research needs, such as the lack of a consistent comparative 
sampling of all the ranges and investigations of the information 
available from soil studies in the spruce-fir zone of the southern 
Appalachians are presented. 

Additional keywords : vegetation diversity, grass and heath balds, 
tundra-like species, soil charcoal, transplants. 



INTRODUCTION 

Spruce-fir forests in the southern Appalachians represent a relatively 
minor portion of the native vegetation of the region (cf . to maps by Cooper 
197 9; Saunders 1980) but because it is attractive to humans, it is a 
significant component of the region's vegetational diversity. Since the 
evergreen spruce-fir forest is a series of scattered forest communities 
within the surrounding deciduous forest, it can be considered as a series of 
isolated segments or "islands" in relation to the more extensive boreal 
forest to the north. White, Miller, and Ramseur (1984) have suggested this 
idea in a recent comparison of the variety of plants that are found in ten 
areas they studied from Virginia southward. 

According to current theory of island biogeography, each island 
develops its set of native species and the larger the island, the greater 
its species diversity (MacArthur and Wilson 1967). This would seem a 
reasonable premise for the isolated units of the southern Appalachian 
spruce-fir forests. 

In this paper we will explore some of the knowledge of each of the 
isolated segments of the spruce-fir forest south of Virginia. Emphasis will 
be placed on the differences of these segments, and where indicated, 
suggestions for areas of research needs will be indicated. 



♦Professor, Department of Biology, Western Carolina University, Cullowhee, 
NC. 

The author wishes to thank Dr. J. H. Horton for his valuable 
suggestions for improving the manuscript; Dr. G. A. Smathers for his 
suggestions and information on his soils research; and Mr. L. W. Tucker for 
his technical assistance. 

70 



APPALACHIAN SPRUCE-FIR FORESTS 

Spruce-fir forests extend to sea level in eastern Canada. They occur at 
about 152 m elevation and upward in Maine and continue as isolated units on 
mountain peaks southward. Throughout this region red spruce ( Picea rubens ) 
is the most characteristic tree species. The fir associated with this 
forest is balsam fir ( Abies balsamea ) as far south as West Virginia; from 
there southward a closely allied species, Fraser fir (A. fraseri ) is 
characteristic (Stephenson and Clovis 1983; cf. Thor and Barnett 1974 for 
discussion on sitniliarities of the two species). Throughout the range of 
the spruce-fir forests, spruce dominates on lower elevations and pure stands 
of fir may be observed at the higher elevations (Stephenson and Clovis 
1983). 

In the central Appalachians elevations are insufficient to accomodate 
well developed spruce-fir forests. While comparisons of the northern and 
southern portions of the spruce-fir have been available for some time 
(Oosting and Billings 1951), comparisons of the central Appalachian spruce 
forests with either northern or southern spruce-fir forests were unavilable 
until recently. In their study, Stephenson and Clovis (1983) found the 
speci.es composition, except for absence of fir in West Virginia stands, of 
their study area were not conspicuously different from stands of the Great 
Smoky Mountains to the south nor the White Mountains to the north. They did 
suggest, however, that regional compositional differences could be explained 
by the fact that spruce-dominated communities were extensive enough to 
encompass distributional limits of many of their associated species. 

Very few studies which compare stands of the spruce-fir forest of 
isolated peaks or between different ranges have been conducted. White, 
Miller, and Ramseur (1984) have addressed this question for ten areas that 
are defined by the 5500-foot contour from Virginia southward. They indicate 
that 342 species have been documented for these areas and find species 
richness positively correlated with size of the area, number of peaks, 
maximum elevation, and number of community types present. 

Pittillo and Smathers (1979), in a comparison of a vegetational 
transect across the Balsam Mountains with Whittaker's (1956) vegetational 
transect in the adjoining Great Smoky Mountains, suggested higher species 
richness for the Balsam Mountains. In this comparison, Pittillo found 112 
6pecies in both areas, 118 species were found in the Balsams only, and 64 in 
the Smokies only. This is the pattern that is often mentioned in the 
literature, namely species found only in one area or the other and species 
common to both areas (cf. Oosting and Billings 1951 for northern and 
southern spruce-fir forests; Ramseur 1960 for southern spruce-fir forests; 
and Mcintosh and Hurley for northern spruce-fir of the Catskill Mountains). 

One of the major difficulties in comparative studies is consistency of 
the sampling procedures. In comparing the Balsam study above (Pittillo and 
Smathers 197 9) with Whittaker's study, the objectives and sampling 
procedures are not alike. While the study by White, Miller, and Ramseur 
(1984) updates Ramseur's work using species lists documented in the 
literature, a uniform, adequate plot or transect sampling procedure across 
the range of the spruce-fir forest is needed for definitive comparison. 
Considering the instability caused by the onslaught of the Balsam woolly 
aphid (cf. Hay 1980, Johnson 1980), botanists may have passed a time in 

71 



which a consistent sampling of the southern Appalachian spruce-fir may be 
made. 



SOUTHERN APPALACHIAN SPRUCE-FIR FORESTS 

In this section the ranges that support spruce-fir forests south of 
Virginia (see Rheinhardt's discussion of the spruce-fir in Virginia 
elsewhere in this volume) will be briefly discussed along with papers 
directed specifically to these localized areas. An attempt to compile the 
appropiate papers is based for the most part on the titles or the knowledge 
of the paper. There are many papers that entailed studies in many of the 
ranges, but the title did not suggest the appropiate range. The bulk of the 
citations are from those by McCrone, Huber and Stocum (1982), Peet (1979), 
and DeYoung, White, and DeSelm (1982). Papers that dealt with community 
types within the area of the spruce-fir zone are included in this report. 
Among them are papers of the spruce-fir communities, fir communities, mixed 
hardwood/conifer (including spruce or fir of course), the grass and heath 
bald communities, and ecotones associated with the spruce-fir communities. 
Not included are the hardwood forest communities such as beech and buckeye 
gap communities nor northern red oak types ("oak orchards"), etc., though 
they do fall within the same general zone. Where the natural presence of 
spruce or fir has been observed by the author, the range is included in the 
discussion. There are reports of spruce or Fraser fir that are not natural 
stands in the literature (e. g. Bruce 1977; DeVore 1972) and there are 
several transplanted poplulations that may now be reproducing (see 
discussion under "Transplants" below). 

One of the active areas of investigation is the question relating the 
origin and maintenance of grass balds. While there are a diversity of ideas 
on the origin of the grass balds (cf. recent papers in the conference volume 
edited by Saunders 1980), and although investigators differ in approaches to 
methods of grass maintenance on these balds, all are agreed that there is 
extensive diminishing of the number and size of southern Appalachian grass 
balds. Many have emphasized fire as the primary factor in bald maintenance, 
although this alone does not seem to be completely effective in maintaining 
the grass against invasion of heath, hardwood trees, nor spruce-fir forest. 
Recently Garrett Smathers has been looking for the presence of charcoal and 
has been observing the general characteristics of the soil in grass balds, 
heath balds, and adjacent northern hardwood and spruce-fir forests. At the 
Spruce-Fir Workshop in the Great Smoky Mountains National Park research 
meeting May 20, 1983, we pointed out that charcoal was present in all the 
community types evaluated (Smathers and Pittillo 1984). It was also pointed 
out that slopes exceeding 40% generally lacked a B horizon. Thus we 
indicate that that studies of soils, such as presence of charcoal, horizon 
characteristics, and the like will likely provide us with clues of the 
history of communities within the spruce-fir zone and help guide our 
management procedures for these areas . 

Great Smoky Mountains 

No segment of the spruce-fir forest has been more studied than that of 
the Great Smoky Mountains. It would seem logical that this is the case: 
here is the greatest extent of the spruce-fir forest in the entire southern 
Appalachian region. This high mountain wilderness was not explored by 

72 



botanists until around the turn of the century, unlike the more settled 
regions to the east. Horace Kephart came to this area in 1904, according to 
Ellison (1976). Kephart and others realized the value of this wilderness 
and many people began to make the suggestion that a national park be 
established here before this entire wilderness was logged. At about the 
time of the establishment of the park, Gaylon (1928), Cain (1930), Camp 
(1931), and Sharp (1939) began their studies of the vegetation of the 
Smokies. So it was in the 1930's and 1940's that we see the appearence of 
numerous studies of plants and vegetation of the area, including that of the 
spruce-fir zone (Cain 1935; Cain 1936; Cain 1945; Cain and Miller 1933; Camp 
1936; Griggs 1942; Miller 1942; Roberts 1940; Sharp 1941; Wells 1936; 
Whittaker 1948; and Yard 1942). Studies were somewhat more numerous in the 
1950's and 1960's (Bruhn 1964; Crandall 1957; Crandall 1958; Crandall 1960; 
Crandall 1965; Davis 1966; Hoffman 1959; Gilbert 1954; Griffin 1965; Lambert 
1961; MacDonald 1967; Norris 1964; Radford 1968; Rudolph 1963; Schofield 
1960; Stephens 1969; Whittaker 1963; and Wolfe 1967) but with the press for 
protection of the wilderness and the onrush of wilderness experiences by 
masses of people, renewed studies of the impact of humans and their 
introduced animals expanded immensely in the 1970's and continues into the 
1980's (Bogucki 1970; Boner 1979; Bratton 1974; Bratton and White 1980; 
Bratton, White, and Harmon 1981; Bratton and Whittaker 1977; DeSelm, 
Amundsen, and Krumpe 1972; Dey 197 8; Eager and Hay 1977; Eager 197 8; Fuller 
1977; Gant 197 8; Golden 1974; Hay 1978; Hay, Eager and Johnson 1976; Huber 
1976; Johnson 1977; Lindsay 1976; Lindsay 1977; Lindsay 197 8; Lindsay and 
Bratton 1979a; Lindsay and Bratton 1979b; Lindsay and Bratton 1980; 
McCracken 1978; Nichols 1977; Pavlovic 1981; Ramseur 1976; Stratton and 
White 1982; White 1982a; White 1982b; and White, Miller, and Ramseur 1984). 



Co wee Mountains 

The natural presence of spruce in the Cowees is not generally known. 
Bruce (1977) in his investigation of pygmy salamanders did not note the red 
spruce in the Cowee Bald area although the pygmy salamander is normally 
associated with spruce-fir forests. Unlike most of the spruce stands in the 
adjacent mountain ranges, the mixed-spruce/hardwood/hemlock stand here 
occurs in the valley flats north of Cowee Bald peak. Only one other location 
in our area is characterized by presence of spruce in the valley flats 
rather than on the slopes and peaks (see the discussion of Long Hope Valley 
in the Blue Ridge Range below) . 

Balsam Mountains 

Several studies have been conducted in the Balsam Mountains. Most of 
this work has been carried out during the past decade, after easy access was 
made possible by completion of the Blue Ridge Parkway. Phil Gersmehl (1970) 
made a significant study of the establishment of spruce and fir seedlings in 
the Judaculla Fields on the west side of Richland Balsam. A significant 
understanding of the dynamics of biomass and nutrient movements within the 
spruce and yellow birch boulderfield communities was carried out by George 
Weaver in 1972. Weaver and DeSelm (1973) briefly described this project at 
the Orono conference. Pittillo and Smathers (1979a) presented a 
phytogeographic description of the Balsams, outlining the vegetational types 
encountered on a transect from the French Broad River floodplain up through 
the spruce fir forest. Larry Barden (1978) investigated the effects of fire 

73 



in maintaining grassy balds after prescribed burning. A study on the 
dispersal of spruce and fir seeds was carried out by Sullivan in 1979 in the 
same area in which Gersmehl did his studies earlier (Sullivan, Pittillo and 
Smathers 1980). Lynn Gaines Hortling (Horton and Gaines 1981) described the 
floristics of the heath communities in Graveyard Fields, comparing these 
with Flat Laurel Gap further north on the Pisgah Ridge extension of the 
Balsam Mountains. Very recently Saunders, Smathers, and Ramseur (1983) 
reported results of their study on secondary succession on Waterrock Knob of 
the western portion of the Balsams, known as the Plott Balsams. 

One of the interesting observations of a species occupying the Balsams 
as a component of the spruce-fir forest but not found in the Smokies to the 
west is the presence of pink shell azalea ( Rhododendron vaseyi ). This rare 
shrub is rather frequent in the Cashiers vicinity of the Blue Ridge, 
particularity on Rocky Mountain and to the east (Pittillo 1976). It is also 
found northward in the Blue Ridge at such places as Flat Rock along the Blue 
Ridge Parkway (Pittillo 197 8). Along the Blue Ridge Parkway of Pisgah Ridge 
and the Balsams, rather extensive populations have spread from rocky borders 
into areas that were burned by slash fires of the 1920's to 1940's. The 
farthest west the species has been observed is on Waterrock Knob. 

The Balsams, on the other hand, do not have some species that can be 
found to the west in the Smokies and to the north in the Craggies. Among 
them are mountain club moss ( Lycopodium selago ), spreading avens ( Geum 
radiatum) , and perhaps deerhair bulrush ( Scirpus caespitosus ) (Pittillo 
1978; White 1982a; White 1982b). Perhaps involved in this is the lack of 
cliffside borders where these tundra-like species could find suitable 
habitats for the past centuries when climates have varied between warmer and 
drier (hypsithermal period) and cooler and wetter (glacial dominant 
periods) . 

Great Craggy Mountains 

North of the Great Smoky and Balsam Mountains, the next high mountain 
elevation mass occurs northeast of Asheville in the Great Craggy Mountains. 
This ridge lies perpendicular to the highest mountains in the southern 
Appalachians, the Black Mountains. For some time scientists and others have 
been curious about the lack of spruce-fir forests on the Craggies despite 
their altitudes well above the spruce-fir and hardwoods ecotone. This 
characteristic is quite impressive when one stands on Craggy Pinnacle and 
looks across Craggy Dome, well above the 1670 m elevation where this ecotone 
is usually expected, and views the spruce-fir forests of the Blacks at a 
lower elevation. There are a few scattered Fraser fir trees on the southeast 
slopes of Craggy Dome but no extensive spruce nor fir forests. There are 
some scattered spruce trees and a few stands, but historical records and 
observations indicate all these have either been transplanted here or 
originated from seeding from planted trees. 

There have been a few studies conducted on the Craggies. Kring (1965) 
addressed the problem of maintaining the rhododendron due to succession by 
trees such as mountain ash in this famous natural garden. Thomas (1982) 
further investigated the replacement of the rhododendron by beech. Efforts 
are underway to continue the studies that deal with the maintenance of the 
purple rhododendron ( Rhododendron catawbiense Michaux) (Smathers 1979). 



74 



The Craggies , as implied by their name, are replete with numerous rocky 
crags and cliffs. Apparently this was a suitable habitat for survival of 
many of the tundra type of vegetation. As mentioned above, mountain club 
moss, deerhair bulrush, and spreading avens frequent these habitats. Also 
found here is a small population of bigtooth aspen ( Populus grandidentata , 
a species not heretofore reported in the literature for this area), a 
species more common in the ecotonal communities bordering northern prairies 
or following fires in the northern states. The presence of bigtooth aspen in 
these areas is generally interpreted as glacial relicts. Likewise, the 
presence of single-flowered rush ( Juncus trif idus var. monanthos , which has 
been redesignated as J_j_ trif idus subsp. carolinianus recently by Hamet-Ahti, 
1980) also reflects this relict characteristic because the species is an 
"arctic-oroarctic ("arctic-alpine") amphi-atlantic species" (Hamet-Ahti 
1980). There are additional rare species for this region that make up a 
component of this unique area, including Carex biltmoreana , C. misera, 
Lilium grayi , Prenanthes roanensis , Saxifraga carevana , etc. (cf. Pittillo 
1978). 



Black Mountains 

Scientists have been attracted to this highest southern Appalachian 
mountain mass since the survey made famous here by Elisha Mitchell in the 
1800's. Eggleston (1908) described his early observations he made in the 
area and with the destructive logging of the Blacks, Pratt and Holmes (1914) 
questioned whether the spruce-fir forest of Mt. Mitchell could be saved. 
The vegetation of the Black Mountains was Davis' 1929 dissertation topic 
(Davis 1929; Davis 1930). The recent balsam woolly aphid infestation and 
applications of pesticides was followed up by a study of the BHC insecticide 
movement by Jackson, Sheets, and Moffett (1974). 

The spruce-fir forests of the crest of the Black Mountains are 
primarily comprised of wind-pruned red spruce or Fraser fir. There seem to 
be fewer rare species, perhaps related to the generally dense spruce-fir 
stands or to the relatively low diversity of community types (e. g. White, 
Miller, and Ramseur [1984] note only three types here compared to eight for 
the Smokies). One notable species of this range is the northern hardwood 
species, paper birch ( Betula papyrifera var. cordifolia ) . This paper birch 
population is much larger than the population in the Smokies, which is the 
only other known for the area under consideration here (White 1982). 

Blue Ridge Mountains 

The Blue Ridge Mountain Range (the narrow series of ridges of the Blue 
Ridge Province occurring along the scarp front from the Dahlonega Plateau in 
Georgia northward to Pennsylvania) has very few peaks that exceed elevations 
sufficient to support spruce-fir forests. Except for the Grandfather 
Mountain area and some peaks north and south of it, elevations of this range 
are below 1525 m. 

Abutting against the Black Mountains, there is a scattering of spruce 
in a mixture of hardwoods and pines that can be observed along the Blue 
Ridge Parkway (Pittillo 1978). It is farther north in the vicinity of 
Grandfather Mountain that the spruce become contiguous and along with Fraser 
fir produce a spruce-fir forest. Since Grandfather Mountain makes a 

75 



prominent feature near the Blue Ridge scarp front, earlier explorers, 
including Andre Michaux (Dugger 1892) and Asa Gray (Gray 1842), were 
attracted to this location and gave us some of our earliest observations and 
documentation of the flora for this area. 

Grandfather Mountain has been an area of interest to many, in part due 
to the advertisement it receives from private enterprise. The bulk of the 
mountain mass remains in natural condition with only the southern tip of the 
peak developed. This is the basis of its recommendation as a National 
Natural Landmark (Pittillo 1976). There are numerous cliffs and craigs here 
and as in the Craggies, there seems to be a complement of tundra-like 
species. Roan roseroot ( Sedum rosea var. roanensis ) , Blue ridge goldenrod 
( Solidago spithamaea ), and Heller's gayfeather ( Liatris helleri ) are some 
representative examples (Pittillo 1978). 

Further north in the Blue Ridge on a tributrary of the New River are 
some upland bogs that are located within valley spruce forests. These are 
known as Long Hope Valley bogs, recognized as a National Natural Landmark. 
The vegetational composition here is unusual in that several northern 
species have their southernmost populations present. Among them is Canada 
yew ( Taxus canadensis ) , bogbean ( Menyanthes trifoliata ) , and saxifrage 
( Saxifraga pensylvanica ) . Research on the vegetation is presently being 
carried out by Duke University, University of Tennessee, and Western 
Carolina University botanists. 

Stone Mountains 

West of Grandfather Mountain and across the Blue Ridge Province are the 
Stone and Unaka Mountains. Sometimes Roan Mountain has been referred to the 
Unakas but it lies farther north and perhaps is most closely associated with 
the Stone Mountains. Standing as a significant feature of the Blue Ridge 
Province along the western front, the Roan has likewise attracted many 
botanists, again with Gray among them (Gray 1842). Once their reports got 
into the literature, there followed a succession of investigators. Br it ton 
(1886) was quickly followed by Scribner (1889) investigating grasses. 
Initially the presence of open grasslands on these mountain peaks was 
overlooked since most botanists followed the original pioneer settlers who 
were grazing cattle on these areas. Here in the 1930's began a controversy 
of the best explanation for the origin of southern Appalachian grass balds; 
it has yet to be satisfactorily resolved (cf. Fink 1931; Brown 1938; Brown 
1941; Brown 1953; Gates 1941; Oosting and Billings 1591; Mark 1958a; Mark 
1958b; Mark 1959; Gersmehl 1969; Gersmehl 1970a; Gersmehl 1970b; Gersmehl 
1971; Gersmehl 1973). Specific attention to the spruce-fir forest of Roan 
Bald is given in Castro's 1969 study. 

The cliffy borders on the western exposure of Roan Mountain must have 
served as habitats for some relict tundra-like species. Spreading avens 
( Geum radiatum ) , Roan roseroot ( Sedum roseum ) , bent avens (G_^ geniculatum ) , 
soft three-awned grass ( Trisetum spicatum var. mo lie ) , Gray's lily ( Lilium 
grayi ) . Blue ridge goldenrod ( Solidago spithamaea ) , and Heller's gayfeather 
( Liatris helleri ) contribute to an impressive list of these tundra-like 
species. 



76 



Transplants 

Throughout the southern Appalachians both native and exotic species of 
spruce and fir are cultivated in yards and on tree farms. The Fraser fir 
grows relatively well in the valley floors down to 500 m elevation. It does 
not reproduce here amd may be more suseptable to diseases such as spider 
mite. The red spruce will grow here but not as well. Commonly Norway 
spruce or cultivars of the white spruce (usually sold as 'Colorado blue 
spruce") are seen instead. 

The transplants that are being considered below were those planted with 
the intent of being allowed to naturalize or establish themselves as a part 
of the native or man-assisted natural community. 

Near the southern terminus of the Blue Ridge Range in Georgia Brasstown 
Bald has some scattered transplants of Fraser fir. No report of these are 
known in the printed literature. 

In the Nantahala Range west of Franklin, NC, on Winespring Bald is a 
well established group of Fraser fir transplants. These appear to have been 
planted here in the 1950's or 1960's. 

A report by DeVore (1972) suggested the presence of native Fraser fir 
in the Unicoi Mountains. However, consultation with U. S. Forest Service 
officials indicated these were transplants. The tree sizes vary at this 
site as they might in natural populations, so it is understandable how they 
might be considered native plants. 

Transplants of spruce and fir have been made in other, well established 
ranges that have native spruce-fir forests. In the Smokies, mature and 
reproducing Norway spruce ( Picea abies ) are present on the eastern slopes. 
In the Balsam Mountains native spruce and fir have been established in the 
Black Balsam Knob region of the Graveyard Fields. In the Black Mountains 
transplants following devastating fires of the early 1900's involved many 
trial plantations, among them spruce and fir. In the Craggies, isolated red 
spruce and pure stands can be observed at different locations. 

Thus, field observations should be checked against the human history of 
a given location before suggestions of the "naturalness" of a given stand is 
indicated. 



SUMMARY 

Spruce-fir forests in the Appalachians generally represent a minor 
portion of forests of the region, are scattered and isolated segments 
distributed on increasingly higher elevations southward, and seem to fit the 
pattern of current theory of island biogeography . In the southernmost 
portions of the Appalachians the spruce-fir component starts at about the 
1675 m contour and since the highest peak is 2038 m, the amount of area is 
rather limited. Likewise, since the available mass is broken up by peaks of 
the several ranges that extend above the 1675 m contour, the spruce-fir 
forest can be thought of as a series of isolated segments or "islands." In 
this paper we have looked at some of the differences that make up each 
spruce-fir community of the various ranges and discover some parallels with 

77 



the theory of island biogiography. The main point made here is that the 
various range spruce-fir communities have their expected common species but 
each one has some unique or restricted species. Evaluation of species 
diversity, a second major component of island biogeography theory, was not 
considered here. 

Studies that compare spruce-fir stands of the different ranges are very 
few. This may be particularly unfortunate with the degeneration of the 
Fraser fir component of the spruce-fir forests. One thing that is especially 
needed is a consitent sampling procedure throughout the entire range of 
southern Appalachian spruce-fir forests. 

Additionally studies that search for clues of the past history of the 
communities that make up the spruce-fir zone are needed. The presence of 
charcoal and lack of a B horizon on steep slopes indicate inadequate 
previous investigation of available field data. 

The discussion of the seven ranges that harbor spruce-fir forests in 
Tennessee and North Carolina included a listing of literature sources for 
each of these ranges as well as some of the notable plant species in each. 
There was extensive literature related to the vegetation of the spruce-fir 
on some of these while others have not been researched and reported 
adequately if at all. The Great Smoky Mountains have the most extensive 
literature (over 50 items are mentioned above) while the one paper 
dealing with an animal usually associated with spruce-fir is the only paper 
for the Cowee Mountains. Two of the ranges, Cowee Mountains and the Long 
Hope Valley of the Blue Ridge, are reported here to contain spruce 
communities for the first time in the literature; one report of native 
Fraser fir for the Unicoi Mountains was indicated to be transplants. 
Finally, a discussion of transplants throughout the southern Appalachians 
indicated that some species from other regions have been introduced and have 
naturalized occasionally while the native red spruce and Fraser fir has been 
established in a number of additional ranges and many additional locations 
within the natural ranges. 



LITERATURE CITED 

Barden, L. S. 197 8. Regrowth of shrubs in grassy balds of the southern 
Appalachian mountains. Castanea 43: 238-246. 

Bogucki, D. J. 1970. Debris slides and related flood damage with the 
September 1, 1951 cloudburst in the Mt. LeConte-Sugarland Mountain area 
Great Smoky Mountains National Park. Ph.D. disssertation, Univ. of Tenn. 
Knoxville. 165 pp. 

Boner, R. R. 197 9. Effects of Fraser fir on population dynamics in southern 
Appalachian boreal ecosystems. M. S. thesis, Univ. of Tenn., Knoxville 
105 pp. 



78 



Bratton, S. P. 1974. The effect of European wild boar ( Sus scropfa ) on the 
high elevation vernal flora in Great Smoky Mountains National Park Bull. 
Torrey Botanical Club 101: 198-206. 

Bratton, S. P. and P. S. White. 1980. Grassy balds management in parks and 
nature preserves: issues and problems. IN P. R. Saunders, ed. Status and 
management of southern Appalachian mountain balds. So. App. Bes./Resour. 
Man. Coop., Western Car. Univ., Cullowhee, NC. Pp. 96-114. 

Bratton, S. P., P. S. White, and M. E. Harmon. 1981. Disturbance and 
recovery of plant communities in Great Smoky Mountains National Park: 
successional dynamics and concepts of naturalness. J_N M. A. Hemstrom and 
J. F. Franklin, eds. Successional research and environmental monitoring 
associated with Biosphere Reserves. US Nat. Comm. for Man and the 
Biosphere, Wash., DC. pp. 42-79. 

Bratton, S. P. and P. L. Whittaker. 1977. Great Smoky Mountains National 
Park: Disturbance and visitation on Mt. LeConte. US Dept. Interior, Nat. 
Park Ser., S. E. Reg. Rept. for Superintendent, GRSM. 59 pp. 

Britton, E. G. 1886. Botanical notes in the great valley of Virginia and 
in the southern Alleghanies. Bull. Torrey Bot. Club 13: 69-76. 

Brown, D. M. 1938. The vegetation of Roan Mountain: an ecological study. 
Ph.D. dissertation, Duke Univ., Durham, NC. 152 pp. 

Brown, D. M. 1941. Vegetation of Roan Mountain: a phytosociological and 
successional study. Ecol. Monogr. 11: 61-97. 

Brown, D. M. 1953. Conifer transplants to a grassy bald on Roan Mountain. 
Ecol. 34: 614-617. 

Bruce, R. C. 1977. The pygmy salamander, Desmognathus wrighti (Amphibia, 
Urodela, Pleithodontidae) in the Cowee Mountains, North Carolina. J. 
Herpetology 11: 246-247. 

Bruhn, M. E. 1964. Vegetational succession on three grassy balds of the 
Great Smoky Mountains. M. S. thesis, Univ. of Tennessee, Knoxville, TN. 
84 pp. 

Cain, S. A. 1930. An ecological study of the heath balds of the Great 
Smoky Mountains. Butler Univ. Bot. Studies 1: 177-208. 

Cain, S. A. 1935. Ecological studies of the vegetation of the Great Smoky 
Mountains. II. The quadrat method applied to the sampling spruce and fir 
forest types. Am. Midi. Nat. 16: 566-584. 

Cain, S. A. 1936. Ecological work on the Great Smoky Mountain region. 
Castanea 1:25-32. 

Cain, S. A. 1945. A biological spectrum of the flora of the Great Smoky 
Mountains National Park. Butler Univ. Bot. Studies 7: 11-24. 



79 



Cain, S. A. and J. D. 0. Miller. 1933. Leaf structure of Rhododendron 
catavbiense Michx. grown in Picea - Abies forest and heath communities. Am. 
Midi. Nat. 14:69-82. 

Camp, W. H. 1931. The grass balds of the Great Smoky Mountains of 
Tennessee and North Carolina. Ohio J. of Sci. 31: 157-164. 

Camp, W. H. 1936. On Appalachian trails. J. Nev York Bot. Garden 37: 
249-265. 

Castro, P. A. 196 9. A quantitative study of the subalpine forest of Roan 
and Bald Mountains in the southern Appalachians. M. S. thesis, East 
Tenn. State Univ., Johnson City, TN. 60 pp. 

Cooper, A. W. 197 9. The natural vegetation of North Carolina. IN Landolt, 
E. and H. Lieth, eds. Vegetation and flora of the Carolinas. Veroff. 
Geobot. Inst. ETH, Stiftung, Rubel, Zurich 68: 70-78. 

Crandall, D. L. 1957. Ground vegetation patterns of the spruce-fir area of 
the Great Smoky Mountains National Park. Ph.D. Dissertation, Univ. of 
Tennessee, Knoxville, TN. 117pp. 

Crandall, D. L. 1958. Ground vegetation patterns of the spruce-fir area of 
the Great Smoky Mountains National Park. Ecol. Monogr. 28: 337-360. 

Crandall, D. L. 1960. Ground vegetation patterns of the spurce-fir area of 
the Great Smoky Mountains National Park. Va. J. Sci. 11: 9-18. 

Crandall, D. L. 1965. Ecological studies in the Great Smoky Mountains. 
Assoc. Southe. Biol. Bull. 12: 63-65. 

Davis, M. C. 1966. Forest of the Smokies. Living Wilderness 30: 6-9. 

Davis, J. H. ,Jr. 1929. Vegetation of the Black Mountains of North 
Carolina. Ph.D. dissertation, Univ. of Chicago, Chicago. 130 pp. 

Davis, J. H., Jr. 1930. Vegetation of the Black Mountains of North 

Carolina: an ecological study. J. Elisha Mitchell Sci. Soc. 45: 291-318. 

DeSeltn, H. R. , C. C. Amundsen, and P. F. Krumpe. 1972. Remote sensing of 
Appalachian wildland resources. Proc. Conf . Earth Res. Obs. and Infor. 
Anal. System. Univ. of Tenn. Space Inst., Tullahoma, TN. Remote Sens, of 
Ear. Res. 1: 193-205. 

DeVore, J. E. 1972. Fraser fir in the Unicoi Mountains. Castanea 
37:148-149. 

Dey, J. P. 1978. Fruticose and foliose lichens of the high mountain areas 
in the southern Appalachians. Bryol. 81: 1-93. 

DeYoung, H. R. , P. S. White, and H. R. DeSelm. 1982. Vegetation of the 
southern Appalachians: An indexed bibliography, 1805-1982. Nat. Park 
Ser., Southe. Reg. Off., Res. Resour. Man. Rept. SER-63. 94 pp. 



80 



Dugger, S. M. 1892. The balsam groves of the Grandfather Mountains. J. of 
Andre Michaux. J. B. Lippincott, Philadelphia, PA. 187 pp. (144-160). 

Eagar, C. C. 1978. Distribution and characteristics of balsam wooly aphid 
infestations in the Creat Smoky Mountains. M. S. Thesis, Univ. of 
Tennessee, Knoxville. 72 pp. 

Eagar, C. C. and R. Hay. 1977. Distribution of the balsam woolly aphid in 
the GSMNP. Third ann. Sci. Res. Mtg., NPS-SER. Great Smoky Mountains 
National Park, Gatlinburg, TN. 22 pp. 

Eggleston, W. W. 1908. A trip to Mt. Mitchell. Vermont Bot. Club Bull. 
3:40-42. 

Ellison, G. 1976. Introduction. J_N Kephart, H. Our southern highlanders. 
The Univ. of Tennessee Press, Knoxville, TN. 469 pp. (Pp. ix-xlviii). 

Fink, P. 1931. The forest enigma. Am. For. 37: 538 and 536. 

Fuller, R. D. 1977. Why does spruce not invade the high elevation beech 
forests of the Great Smoky Mountains? M. S. Thesis, Univ. of Tennessee, 
Knoxville. 65 pp. 

Gates, W. H. 1941. Observations of the possible origin of the balds of the 
southern Appalachians. Contributions from the Dept. of Zoology, La. State 
Univ. 53: 1-16. 

Gay Ion, W. L. 1928. The Smoky Mountains and the plant naturalist. J. 
Tenn. Acad. Sci. 3: 3-13. 

Gant, R. E. 1978. The role of allelopathic interference in the maintenance 
of southern Appalachian heath balds. Ph.D. Dissertation, Univ. of 
Tennessee, Knoxville. 123 pp. 

Gersmehl, P. J. 196 9. A geographic evaluation of the ecotonal hypothesis 
of bald location in the southern Appalachians. Assoc. Am. Geogr. Proc . 1: 
51-54. 

Gersmehl, P. J. 1970a. Factors involved in the persistence of southern 
Appalachian treeless balds: an experimental study. Assoc. Am. Geogr. 
Proc. 3: 56-61. 

Gersmehl, P. J. 1970b. Factors leading to mountain top grazing in the 
southern Appalachians. Southe. Geogr. 10: 67-72. 

Gersmehl, P. J. 1971. A geographic approach to a vegetation problem: The 
case of the southern Appalachian grassy balds. Ph.D. dissertation, Univ. 
of Ga., Athens, GA. 463 pp. 

Gersmehl, P. J. Pseudo-timberline: The southern Appalachian grassy balds. 
Arctic and Alpine Res. 5: A 137- A 138. 

Gilbert, V. C. Jr. 1954. Vegetation of the grassy balds of the Great Smoky 
Mountains National Park. M. S. Thesis, Univ. of Tenn., Knoxville. 73 pp. 



81 



Golden, M. S. 1974. Forest vegetation and site relationships in the 

central portion of the Great Smoky Mountains National Park. M. S. Thesis, 
Univ. of Tennessee, Knoxville. 275 pp. 

Gray, A. 1842. Notes on a botanical excursion to the mountains of North 
Carolina. Am. J. Sci. and Art 42: 1-49. 

Griffin, N. C. W. 1965. Germniation and early survival of Picea rubens 
Sargent in experimental and field plantings. M. S. Thesis, Univ. of 
Tennessee, Knoxville. 44 pp. 

Griggs, R. F. 1942. "Dr. Griggs on the problem of balds." IN R. S. Yard, 
Living Wilderness 7: 15. 

Hay, R. C. et al. 1978. Fraser fir in the Great Smokies, Univ. of Tenn. 
Press, Knoxville, TN. 125 pp. 

Hamet-Ahti, L. Juncus trifidus L. ssp. carolinianus Hamet-Ahti, n. subsp., 
in eastern North America. J_N Lieth, H. and E. Landolt, eds. Contributions 
to the knowledge of flora and vegetation in the Carolinas. Veroff. Geobot. 
Inst. Eth., Stiftung Rubel, Zurich 69: 7-13. 

Hoffman, H. L. 1959. Boreal forest vascular plants which are also native 
to the Great Smoky Mountains. Typewritten report, Univ. of Tennessee, 
Knoxville. 

Horton, J. H. and L. H. Gaines. 1981. Floristics of selected heath 

communities along the southern section of the Blue Ridge Parkway. National 
Park Ser. Res./ Resour. Manage. Rep. 45. 

Huber, F. C. 1976. Rare and endangered plant species and special 

protection areas in the Great Smoky Mountains National Park. Second Ann. 
Sci. Res. Mtg. Nat. Park Ser., Southeast Reg. Gr. Sm. Nat. Pk., 
Gatlinburg, TN. 

Jackson, M. D., T. J. Sheets, and C. L. Moffett. 1974. Persistence and 
movement of BHC in a watershed, Mount Mitchell State Park, North 
Carolina — 1967-72. Pest Monitoring J. 8: 202-208. 

Johnson, K. D. 1977. Balsam woolly aphid infestation in Fraser fir in the 
Great Smoky Mountains. M. S. Thesis, Univ. of Tennessee, Knoxville. 64 
pp. 

Johnson, K. D. 1980. Fraser fir and balsam woolly aphid — summary 
information. So. App. Res. /Resour. Manag. Coor. , Univ. of Tenn., 
Knoxville, TN. 

Kring, J. B. 1965. Vegetational succession at Craggy Gardens, North 
Carolina. M. S. thesis, Univ. of Tenn., Knoxville. 61 pp. 

Lambert, R. S. 1961. Logging in the Great Smokies, 1880-1930. Tenn. Hist. 
Quart. 20: 350-363. 

Lindsay, M. 1976. History of the grassy balds in the Great Smoky Mountains 
National Park. Nat. Park Service, Southeast Reg. Man. Rept 4. 215 pp. 



82 



Lindsay, M. 1977. Management of grassy balds in Great Smoky Mountains 
National Park. Nat. Park Service, Southeast Reg. Man. Rept. 17. 67 pp. 

Lindsay, M. 197 8. The vegetation of the grassy balds and other high 
elevation disturbed areas in the Great Smoky Mountains National Park. 
Nat. Park Service, Southeast Reg. Man. Rept. 26. 150 pp. 

Lindsay, M. and S. P. Bratton. 1979a. Grassy balds of the Great Smoky 
Mountains: their history and flora in relation to potential management. 
Env. Manag. 3: 417-430. 

Lindsay, M. M. and S. P. Bratton. 1979b. The vegetation of grassy balds 
and other high elevation disturbed areas of the Great Smoky Mountains 
National Park. Bull. Torrey Bot. Club 106: 264-275. 

Lindsay, M. and S. P. Bratton. 1980. The rate of woody plant invasion in 
two grassy balds. Castanea 45: 75-87. 

MacDonald, M. E. B. 1967. Grass balds of the Great Smoky Mountains. The 
Univ. of Tenn. Arboretum Soc . Bull., summer 1967. 6 pp. 

Mark, A. F. 1958a. An ecological study of the grass balds of the southern 
Appalachian Mountains. Ph.D. dissertation, Duke Univ., Durham, NC. 284 
pp. 

Mark, A. F. 1958b. The ecology of southern Appalachian grass balds. Ecol. 
Monogr. 28: 293-336. 

Mark, A. F. 1959. The flora of the grass balds and the fields of the 
southern Appalachian mountains. Castanea 24: 1-21. 

McCracken, W. H. , III. 1978. Comparison of forest cover prior to and 
following disturbance in two areas of the Great Smoky Mountains National 
Park. M. S. thesis, Univ. of Tenn., Knoxville. 87 pp. 

Miller, F. H. 1942. Vegetation map of the Great Smoky Mountains National 
Park. Archives, Visitor Center, Gatlinburg, TN. 

Nichols, R. 1977. The ecological effects of LeConte lodge in the Great 
Smoky Mountains National Park. National Park Service, Southe. Reg. Off. 

Norris, D. H. 1964. Bryoecology of the Appalachian spruce-fir zone. Ph.D. 
discertation, Univ. of Tenn., Knoxville. 175 pp. 

Oosting, H. J. and W. D. Billings. 1951. A comparison of virgin spruce-fir 
forest in the northern and southern Appalachian system. Ecol. 32: 84-103. 

Pavlovic, N. B. 1981. An examination of the seed rain and seed bank for 
evidence of seed exchange between a beech gap and a spruce forest in the 
Great Smoky Mountains. M. S. thesis, Univ. of Tenn., Knoxville. 

Peet, R. K. 1979. A bibliography of the vegetation of the Carolinas. IN 
Landolt, E. and H. Lieth, eds. Contributions to the knowledge of flora 
and vegetation in the Carolinas. Veroff. des Geobot. Inst, der ETH, 
Stiftung Rubel, Zurich 68: 263-297. 

83 



Peet, R. K. 1980. A bibliography of the vegetation of the Carolinas, 
supplement I. J_N Landolt, E. and H. Lieth, eds. Contributions to the 
knowledge of the flora and vegetation of the Carolinas. Veroff. des 
Gebot. Inst, der ETH, Stiftung Rubel, Zurich 69: 183-186. 

Pittillo, J. D. Potential natural landmarks of the southern Blue Ridge 
portion of the Appalachian Ranges natural region. Nat. Park Serv., 
Southe. Reg. Off., Atlanta, GA. 372 pp. 

Pittillo, J. D., and G. A. Smathers. 1979a. Phytogeography of the Balsam 
Mountains and Pisgah Ridge, southern Appalachian Mountains. IN Landolt, E. 
and H. Lieth, eds. Vegetation and flora of the Carolinas. Veroff. Geobot. 
Inst. ETH., Stiftung, Rubel, Zurich 68: 79-107. 

Pittillo, J. D., and G. A. Smathers. 1979b. Vegetational patterns of the 
balsam and Great Smoky Mountains of the southern Appalachians. Second 
Conf. on Sci. Res. in National Parks, San Francisco, CA. 4: 307-322. 

Pratt, J. H. and J. S. Holmes. 1914. Can't Mt. Mitchell's spruce forests 
be saved? N. C. Geol. and Econ. Surv. Bull. No. 135. 4 pp. 

Radford, S. W. 1968. Factors involved in the maintenance of the grassy 
balds of the Great Smoky Mountains National Park. M. S. thesis, Univ. of 
Tenn., Knoxville. 74 pp. 

Ramseur, G. S. 1960. The vascular flora of high mountain communities of 
the southern Appalachians. J. Elisha Mitchell Sci. Soc. 76: 82-112. 

Ramseur, G. S. 1976. Secondary succession in the spruce-fir forest of the 
Great Smoky Mountains National Park. National Park Ser., Southe. Reg. 
Off. GRSM Manag. Rept. No. 7. 35 pp. 

Roberts, E. V. 1940. Appalachian forest experiment station: Major forest 
types of the states in the region. U. S. D. A., Forest Service, App. For. 
Expt. Sta. 

Rudolph, W. K. 1963. Concentrations of gamma-emitting fallout 

radionuclides from Pice rubens and Rhododendron maximum of the Great Smoky 
Mountains. M. S. thesis, Univ. of Tenn., Knoxville. 3 8 pp. 

Saunders, P. R. , G. A. Smathers, and G. S. Ramseur. 1983. Secondary 
succession of a spruce-fir burn in the Plott Balsam Mountains, North 
Carolina. Castanea 48: 41-47. 

Saunders, P. R. , ed. 1980. Status and management of southern Appalachian 
Mountain balds. Proc. So. App. Res./Resour. Man. Coop., Western Carolina 
Univ., Cullowhee, NC. 124pp. 

Schofield, V7. B. 1960. The ecotone between spruce-fir and deciduous forest 
in the Great Smoky Mountains. Ph.D. dissertation, Duke Univ., Durham, NC. 
176 pp. 



84 



Scribner, F. L. 1889. The grasses of Roane Mountain. Bot. Gaz. 14: 
253-255. Sharp, A. J. 1939. Taxonomic and ecologic studies of eastern 
Tennessee bryophytes. Am. Midi. Nat. 21: 267-354. 

Sharp, A. J. 1941. The Great Smoky Mountains National Park, an important 
botanical area. Chronica Botanica 6: 296-297. 

Smathers, G. A. 1979. Craggy Gardens study. National Park Ser., Res./ 
Resour. Info. Bull. No. 4. 5 pp. 

Smathers, G. A. and J. D. Pittillo. 1984. Role of perturbations in the bald 
formation of the southern Appalachians. Ninth Ann. Sci. Res. Mtg., Nat. 
Park Ser., Southe. Reg. Off., Atlanta, (abstract). 

Stephens, L. A. 1969. A comparison of climatic elements at four elevations 
in the Great Smoky Mountains National Park. M. S. thesis, Univ. of Tenn. , 
Knoxville. 119 pp. 

Stratton, D. A. and P. S. White. 1982. Grassy balds of the Great Smoky 
Mountains National Park: vascular plant floristics, rare plant 
distribution, and an assessment of the floristic data base. Nat. Park 
Ser., Southe. Reg. Off. Res. /Resour. Manage. Rept. Series. 

Sullivan, J. H. , J. D. Pittillo, G. A. Smathers. 1980. Dispersal and 
establishment of red spruce and Fraser fir in three bald areas of the 
southern Appalachians. National Park Ser. Res./ Resour Manag. Rept. 

Thomas, R. B. 1982. Invasion of beech into a high elevation heath bald at 
Craggy Gardens, North Carolina. M. S. thesis, Western Car. Univ., 
Cullowhee, NC. 57 pp. 

Weaver, G. T. 1972. Dry matter and nutrient dynamics in red spruce-Fraser 
fir and yellow birch ecosystems in the Balsam Mountains, western North 
Carolina. Ph.D. dissertation, Univ. of Tenn., Knoxville. 406 pp. Wells, 
B. W. 1936. Andrews Bald: the problem of its origin. Castanea 1: 59-62. 

White, P. S. 1982a. New and noteworthy plants from Great Smoky Mountains 
National Park, North Carolina and Tennessee. Castanea 47: 78-83. 

White, P. S. 1982b. The flora of Great Smoky Mountains National Park: an 
annotated checklist of the vascular plants and a review of previous 
floristic work. Nat. Park Ser., Southe. Reg. Off. Res. /Resour. Man. Rept. 
SER-55. 219 pp. 

White, P. S., R. I. Miller, and G. S. Ramseur. 1984 (in press). The 

species-area relationship of the southern Appalachian high peaks: Vascular 
plant richness and rare plant distributions. National Park Ser., Uplands 
Field Research Lab, Great Smoky Mountains National Park, Gatlinburg. 27 
pp. typescript. 



85 



Whittaker, R. H. 1948. A vegetation analysis of the Great Smoky Mountains. 
Ph.D. dissertation, Univ. of 111., Urbana. 478 pp. 

Whittaker, R. H. 1956. Vegetation of the Great Smoky Mountains. Ecol. 
Monogr. 26: 1-80. 

Whittaker, R. H. 1963. Net production of heath balds and forest heaths in 
the Great Smoky Mountains. Ecol. 44: 176-182. 

Wolfe, J. A. 1967. Forest soil characteristics as influenced by vegetation 
and bedrock in the spruce-fir zone of the Great Smoky Mountains. Ph.D. 
dissertation, Univ. of Tenn. , Knoxville. 193 pp. 

Yard, R. S. 1942. The Great Smoky wilderness. The Living Wilderness 7: 
7-19. 



86 



COMPARATIVE STUDY OF COMPOSITION AND DISTRIBUTION 

PATTERNS OF SUBALPINE FORESTS IN THE BALSAM MOUNTAINS 

OF SOUTHWEST VIRGINIA AND THE GREAT SMOKY MOUNTAINS 

Richard D. Rheinhardt 



Abstract . The vegetation of subalpine forests in the 
Balsam Mountains (Mount Rogers and Whitetop) in southwest 
Virginia were examined and compared to similar forests in 
the Great Smoky Mountains. Differences in latitude and 
longitude were considered in comparing zonal distribution 
patterns. 

A spruce-fir ( Picea rubens-Abies f raseri ) forest on 
Mount Rogers is similar in composition and distribution to 
those of the Great Smokies at equivalent elevations. In 
contrast to Mount Rogers, Whitetop's subalpine forests are 
devoid of fir, although the upper 158 m (520')seem 
environmentally suitable for its growth. It is believed 
that during the post-Wisconsin xerotherraic period, fir was 
eliminated from Whitetop, but found refuge on the taller 
Mount Rogers. Although fir has been able to extend its 
range downward since the xerothermic period, it has been 
unable to cross the relatively low elevation gap separating 
the two mountains. 

Spruce forests, which were expected to cover slopes 
between 1190 m (3900') and 1525 ra (5000') in the Virginia 
Balsams, do not extend below 1430 m (4700'). This 
seemingly truncated distribution might be a result of past 
human disturbance, but no substantive evidence is 
available. 

The future structure of some aphid-infested spruce-fir 
forests in the southern Appalachians may be predicted by 
examining the spruce forests on Whitetop, particularly at 
elevations which are suitable for the development of 
spruce-fir forests. Since Mount Rogers' firs appear to be 
resistant to aphid devastation, the spruce-fir forest there 
may some day be the only surviving representative of this 
type of ecosystem. If the resistance to aphid induced 
death is genetic, and preserving the structural integrity 
of the spruce-fir ecosystem is deemed important, 
repopulating aphid-infested areas with fir seeds from Mount 
Rogers might be considered. 

Additional keywords : Abies f raseri , Picea rubens , southern 
Appalachians, vegetation, xerothermic period, zonal 
distribution. 



1/ 

Biology Department, William and Mary College, Williamsburg, 

Virginia 

87 



INTRODUCTION 

The southern Appalachian subalpine spruce-fir (Picea rubens-Abies 
fraseri) forests are restricted to seven high elevation mountain areas 
between Mount Rogers in the Virginia Balsams and Double Springs Gap the 
Great Smoky Mountains (Ramseur 1960). These isolated forest 
communities are remnants of a boreal forest ecosystem which was 
widespread throughout the southern Appalachians during the Pleistocene 
glaciations. Since the last glacial retreat, ten to fifteen thousand 
years ago, these subalpine communities have been subjected to different 
biological and anthropogenic pressures. 

Most phytosociological investigations of southern Appalachian 
subalpine forests have focused on mountain areas south of Virginia: on 
Roan Mountain (Brown 1951), in the Black Mountains (Davis 1930, Braun 
1950), the North Carolina Balsam Mountains (Pittillo and Sraathers 
1979), and the Great Smoky Mountains (Cain 1935, Braun 1950, Crandall 
1958, Whittaker 1956). Although floristic comparisons have been made 
among southern Appalachian subalpine stands (Ramseur 1960) and between 
virgin stands in the Great Smokies and the White Mountains of New 
Hampshire (Oosting and Billings 1957), little in the way of 
compositional and distributional comparisons between these isolated 
communities have been attempted. Recently, however, Stephenson and 
Adams (1984) published data on the northern-most enclave of the 
southern Appalachian subalpine forest system, those of the Virginia 
Balsams in southwest Virginia (Fig. 1). 

This study compares the composition and distribution of subalpine 
forests located at the geographic extremes of the southern Appalachian 
forest system, those located in the southern part of the range (in the 
Great Smokies) and those located at the northern extreme (in the 
Virginia Balsams). Because little published information is available 
on the Virginia Balsams, a description of the area and its forests is 
presented. 

The Balsam Mountains of southwest Virginia include the two tallest 
and most massive peaks in the state: Mount Rogers (1746 m) and 
Whitetop (1682 m). These northeast-southwest trending mountains are a 
geologically complex system of metamorphosed igneous and sedimentary 
rocks (primarly rhyolite). They are bordered on the north by the Iron 
Mountains (the first range of the Ridge and Valley Province) and on the 
south by the Blue Ridge proper. 

The high elevation north slopes of the subalpine zones of Mount 
Rogers and Whitetop are extremely steep and rugged in contrast to their 
more subdued south slopes. Much of these north slope subalpine forests 
are believed to be virgin because the extreme topography prevented 
logging operations there. Most of the rest of the subalpine forests 
were logged once (circa 1910), although some sections of Whitetop and 
Cabin Ridge (off Mount Rogers) were logged around 1958 (Shields 1960). 
Approximately 400 ha of spruce-fir forest covers Mount Rogers and 
adjacent Pine Mountain and Cabin Ridge, while Whitetop harbors about 
150 ha of spruce forest. (Fig- 2). 



88 




Figure 1 



Location of Mount Rogers of the Virginia Balsams in relation to the 
rest of the southern Appalachians. Reproduced from Braun s (1950 
vegetation map of eastern North America. 



89 





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Since the Virginia Balsams are located approximately 170km 
northeast of the Great Smoky Mountains, equivalent topographic-climatic 
conditions in the Virginia mountains should be about 183 m lower than 
in the Great Smokies (Hoptkins 1938). This value is only approximate 
since vegetation patterns are affected not only by climate and 
topography, but by precipitation regime, humidity, history of use, and 
possibly by the heights of the mountains being compared. 



METHODS 

Quantitative information presented on the Virginia subalpine 
forests are a synthesis of data collected by the author and other 
investigators (from Shields 1960 and unpublished data of Adams 1982). 
Data presented on the Great Smoky Mountains are primarly derived from 
earlier (pre-1960) ecological studies by Cain (1935), Crandall (1958), 
Ramseur (1960), and Whittaker (1956), although some recent data 
collected by the author are included. In order to make a more accurate 
comparison between stands, measurements were standardized to relative 
basal areas whenever possible. It should be noted that comparisons can 
only be of a general nature since sampling methods vary. Taxonomic 
nomenclature follows Radford et al. (1968), except that the taxon 
treated as Amelanchler arborea var. laevis is here reported as 
Amelanchler laevis Wiegand. 

RESULTS 

Quantitative data on the composition of subalpine stands on Mount 
Rogers and in the Great Smokies are presented in Table 1. Stand A on 
Mount Rogers' summit is believed to be virgin. Note its similarity to 
stand F in the Great Smokies. On Mount Rogers, spruce and fir 
generally share dominance at about 1646 m (note stand C), This 
coincides with the 1830 m average isocline of equal basal area 
described by Whittaker (1956) for the Great Smokies. As is the case in 
other southern Applalachian subalpine forests, fir exhibits an increase 
with respect to spruce toward higher elevations, while the total basal 
area of the forest declines. Also, as Whittaker (1956) found in the 
Great Smokies, fir exhibits a greater relative dominance toward more 
mesic sites. Note that in stand D (near a high elevation stream) fir 
shows a much higher relative dominance In comparison to spruce even at 
an elevation well below 1646 m. 

Most quantititive data for the Great Smokies were collected prior 
to 1960. Since 1960, Balsam wooly aphid-infestation has dramatically 
altered the structure of many subalpine forests by killing large 
numbers of canopy-sized Fraser firs. A recently (1983) sampled stand 
on Mt. LeConte in the Great Smokies (stand M, Table 2) exemplifies 
this structural change. Numbers in parentheses include counts of 
standing dead timber, most of which are fir killed by the aphid. This 
forest now resembles the spruce forests on Whitetop in composition 
(note stand K), except that the canopy is more open in aphid-infested 
areas. Surprisingly, Fraser fir on Mount Rogers has not been affected 
by the aphid, although the organism has been present there for over 20 
years (C. Eager, personal communication). 

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93 



Another interesting difference between the subalpine forests of 
the Great Smokies and those of Mount Rogers is that on Mount Rogers, 
spruce is the overwhelming conifer dominant only in a narrow transition 
zone between subalpine and northern hardwood forests. Thus, spruce 
occurs primarly above 1463 m on Mount Rogers, in contrast to the Great 
Smoky Mountains where spruce forests sometimes extends to as low as 
1372 m (the equivalent of 1190 m in the Virginia Balsams). 

In contrast to Mount Rogers, Whitetop's subalpine forests are 
devoid of fir, although the upper 158 m seem environmentally suitable 
for its growth. Red spruce is the sole conifer dominant in subalpine 
forests above 1555 m (Fig. 2). Note stands I and J (Table 2) on 
Whitetop, which are at elevations high enough to support fir. Note 
also the similarity between stand K. on Whitetop and stand M on Mt . 
LeConte (stand M is the former spruce-fir stand which lost almost all 
of its fir to aphid-infestation). 

As is the situation on Mount Rogers, spruce forests on Whitetop do 
not extend to as low an elevation as one might expect based on its 
lower distribution in the Great Smokies. The lower limit of spruce 
forests on Whitetop is 1400 m (along a high elevation flat), which is 
more than 200 m above its predicted limit based on the lower range of 
spruce in the Great Smoky Mountains. 

The herbaceous stratum of subalpine forests of the Balsams are 
similar floristically to those of the Great Smokies. The Virginia 
Balsams, however, lack many of the site-types described by Crandall 
(1958) for the Smokies because subalpine forests in the Balsams are 
less topographically diverse than the Smokies. Open slopes of Mount 
Roger's subalpine forests are dominated by Oxalis acetosella and 
Dryopteris campyloptera (Table 3). Towards less mesic sites, the 
relative importance of Oxalis and Dryopteris decrease as Carex spp . 
increase. Other herbaceous species include Aster divaricatus , 
Clintonia borealis , Arisaema triphyllum , and Lyco podium lucidulum . 

Whitetop's herbaceous vegetation differs somewhat from Mount 
Rogers in that Maianthemum and Thelypteris noveboracensis are 
relatively more important (stand I, Table 3) on Whitetop. When Shields 
(1960) found Maianthemum to be more important in the spruce forests of 
nearby Beartown Mountain than on Mount Rogers, he concluded that 
Beartown was more closely related to more northern subalpine forests 
(this was because Oosting and Billings (1951) included Maianthemum in 
their list of species for the White Mountains, but not for the Great 
Smokies). A more detailed study of Whitetop's herbaceous vegetation 
should be made to determine its position in the vegetational mosaic of 
the Appalachian subalpine system. 



94 



Table 3. Herbaceous composition of subalpine forests in and the Great Smokies 
(N,0,P). Elevations in parentheses are equivalent elevations for the 
Virginia Balsams (VB) and the Great Smoky Mountains (GRSM). Data source 
indicated below. Sp-F = Spruce-fir forest and Sp = Spruce forest. 

Virginia Balsams Great Smokies 

A B D I N P 

Elevation (m) VB 1737 1734 1591 1600 (1737) (1509) (1509) 

GRSM (1920) (1917) (1774) (1783) 1920 1692 1692 

Forest-type Sp-F Sp-F Sp-F Sp Fir Sp-F Sp 

Oxalis acetosella 70.4 
Dryopteris campyloptera 25.7 

Aster acuminatus 3.9 

Carex spp. - 
Clintonia borealis 

Arisaema triphylum - 

Lycopodium lucidulum - 

Other 0.0 



Stands A,D, and I: Data from Rheinhardt (1980); values are averages of relative 

coverage and frequency. 
Stand B: Unpublished data collected by Adams and Stephenson (1982); values are 

averages of relative coverage and frequency. 
Stands N,0,P: Data from Crandall (1958); values were converted from relative 

coverages converted from absolute coverages. 
Includes Rubus canadensis (13.4), Thelypteris noveboracensis (15.9), and 

Maianthemum canadense (14.4). 



51.3 


42.0 


12.7 


43.0 


54.9 


65.9 


35.5 


16.5 


35.6 


22.8 


23.2 


13.5 


4.0 


10.4 


- 


8.2 


0.1 


0.4 


7.7 


10.4 


- 


- 


- 


- 


1.1 


- 


- 


1.7 


0.4 


0.2 


0.6 


4.2 


- 


- 


- 


- 


- 


8.6 


- 


- 


0.1 


1.8 


0.0 


7.8 


51.7 


24.3 


21.3 


18.2 



95 



DISCUSSION 

A comparison of the composition of spruce-fir forests of Mount 
Rogers and the Great Smoky Mountains indicate a close affinity between 
the two areas. The Smokies and the Virginia Balsams differ in that the 
lower distribution of spruce is truncated in the Balsams and fir is 
absent on Whitetop Mountain. 

Mark (1958), in his study of southern Appalachian grass balds, 
found an inverse relationship between the height of a mountain and the 
lower limit of its coniferous forest. Ke suggested that after the 
xerothermic period, lower elevation mountains were left with smaller 
and more "biotype depleted" conifer populations which might be 
relatively poorly adapted to invade downward. If correct, this could 
explain why spruce is restricted to higher elevations in the Virginia 
Balsams in comparison to the mountains of the Great Smokies. However, 
if the spruce population became genetically impoverished during the 
xerothermic period fir must have become even more so. Yet, the lower 
distributional limit of fir is as would be expected if regional 
climatic differences are considered. 

Another possible explanation is that spruce's present distribution 
is related to disturbance history. On the basis of timber extraction 
records and climatological data, Pielke (1981) concluded that spruce 
was once much more extensively distributed in Virginia prior to the 
large scale logging operations of the late 1800s and early 1900s. 
Further, he believes that the commonplace burning of logging debris 
destroyed favorable microclimate and soil conditions necessary for the 
successful germination and growth of spruce. He believes large areas 
of Virginia (above 900 m) were once spruce forests, but are now 
dominated by hardwoods. 

Pielke's conclusions have been met with some skepticism since old 
logging records are unreliable, and often hemlock (Tsujga canadensis) 
and fir were recorded as spruce (Shields 1960). Also, In the Virginia 
Balsams, there is no evidence that spruce is increasing in importance 
in the higher elevation hardwood forests as might be expected. More in 
depth investigations are needed before it can be determined with any 
reasonable certainty whether or not spruce was once more extensively 
distributed in the Virginia Balsams or In the rest of Virginia. 

A possible explanation for the lack of fir on Whitetop is that a 
slight shifting in ecotonal boundaries upward during the last 
post-Wisconsin xerothermic (or hypsi thermic) period may have led to the 
eliminantion of fir from whitetop (Fig. 3). but not spruce (which 
extends to lower elevations than does fir throughout the southern 
Appalachians). Fir might have been able to find refuge on the higher 
summit of Mount Rogers during the xerothermic period. 



96 



pr«-X«rOth«rm«c 



Mount 

Rogtri 



1 700m. . 



Whifetop 



1500irT: 



1300m. 




X«roth«rmic 



1500m. 



1300m. 



1500m_T* 



Mount 
Rogers 



1700m. ) V . h _ i _ ,, _ , .°f. 




1700m. l V . h . i . ,, . , _°_ p . 



1300m.. 



1353 



Figure 3. Presumed changes in the distribution of subalpine forests 
on Whitetop and Mount Rogers caused by climatic conditions 
of the post-Wisconsin xerothermic (or hypsithermic) period 
about 4,000 years ago. Single diagonal lines delimit the 
distribution of spruce forests while cross-hatching 
reresents the distribution of spruce-fir forests. 



97 



Then, when global temperatures again began cooling, fir must have 
extended its range down the slopes of Mount Rogers to its present 
position (182 m lower than the height of Whitetop's summit). It 
appears that fir has been unable to reoccupy the highest elevations of 
Whitetop Mountain, where climatic conditions seem suitable for its 
establishment, because it could not cross the fairly low elevation gap 
(elevation=1347 m) separating Whitetop from Mount Rogers. A similar 
scenario was hypothesized by Whittaker (1956) as having possibly 
occurred in the Great Smokies with respect to both spruce and fir 
versus hardwoods on peaks. 

Subalpine spruce forests on Whitetop are compositional ly similar 
to other forests in the southern Appalachians which were spruce-fir 
forests prior to Balsam wooly aphid-infestation. The primary 

difference between Whitetop's subalpine forests and the others is that 
Whitetop's forests have had more time (about 4,000 yrs.) to reach 
equilibrium. Thus, the subalpine forests of Whitetop may represent the 
future structure of spruce-fir forests in the southern Appalachians 
after recovery from aphid destruction. 

Mount Rogers appears to be unique in that its Fraser firs are able 
to tolerate aphid stress. Perhaps as was during the xerothermic 
period, when the fir population was very low (founder population) that 
an ability to withstand aphid-induced stress became fixed in the 
population- It might therefore be prudent to determine whether or not 
aphid resistance is a genetically acquired trait. If the fir 
population on Mount Rogers does indeed have a genetic propensity to 
withstand aphid-induced stress, and preserving the structural integrity 
of the ecosystem is deemed important, it might be worth investigating 
the possiblity of repopulating aphid-infested areas with seeds derived 
from firs growing on Mount Rogers. 

Fortunately, the subalpine forests of the Virginia Balsams are 
currently protected from human disturbance. Not only does Mount Rogers 
harbor the northern-most enclave of the Southern Appalachian spruce-fir 
forest ecosystem, but the firs there may contain a reservoir of genetic 
material which may one day prove useful in re-establishing this species 
in areas from which they are being eradicated. 



LITERATURE CITED 

Braun , E. L. 1950. Deciduous forests of eastern North America. New 
York' Hafner. 596 pp. 

Brown. D M. 1941. The vegetation of Roan Mountain* A 

phyt osociological and successional study. Ecol Mo nog . 

11-61-97. 

Cain, S- A- 1935. Ecological studies of the vegetation of the Great 

Smoky Mountains . II. The quadrat method applied to sampling 

spruce and spruce-fir forest-types- Am. Midi. Nat. 16- 
566-584. 



98 



Crandall, D. L. 1958. Ground vegetation patterns of the Great Smoky 
Mountain National Park. Ecol. Monog. 28:337-360. 

Davis, J.H., Jr. 1930. Vegetation of the Black Mountains of North 
Carolina: An ecological study. J. Elisha Mitchell Sci. Soc. 
45: 291-318. 

Hoptkins, D. A. 1938. Bioclimatics: a science of life and climate 
relationships. Misc. Publ. #280, Dept. of Agric. 1-188. 

Mark, A. F. 19 58. The ecology of the southern Appalachian grass 
balds. Ecol. Monog. 28(4): 293-336. 

Oosting, H. J. and W. D. Billings. 1951. A comparison of virgin 
spruce-fir forest in the northern and southern Appalachian system. 
Ecol. 32: 84-103. 

Pielke, R.A. 1981. The distribution of spruce in west-central 
Virginia before lumbering. Castanea 46: 201-216. 

Pittillo, J. D. and G.A. Smathers. 1979. Phytogeography of the 
Balsam Mountains and Pisgah Ridge, southern Appalachian Mountains. 
In proceedings of the 16 th International Phytogeographers 
Excursion (IPE) 1978, through the southeastern United States. 
1:206-245. 

Radford, A.E., H.E. Ahles, and C.R. Bell. 1968. Manual of the 
vascular flora of the Carolinas. Chapel Hill, North Carolina: 
The University of North Carolina Press, 1183 pp. 

Ramseur, G. R. 1960. The vascular flora of high mountain communities 
of the southern Appalachians. J. Elis ha Mitchell Sci. Soc. 
76: 82-112. 

Rheinhardt, R.D. 1981. Vegetation of the Balsam Mountains: A 
phytosociological study. Masters Thesis, College of William and 
Mary, 146pp. 

Shields, A.R. 1962. The isolated spruce and spruce-fir forests of 
southwest Virginia: A biotic study. PhD Dissertation, Univ. of 
Tennessee, 174 pp. 

Stephenson, S. L. and H. S. Adams. 1984. The spruce-fir forest on 
the summit of Mount Rogers in southwest Virginia. Bull. Torrey 
Bot. Club 111: 69-75. 

Whittaker, R.H. 1956. Vegetation of the Great Smoky Mountains. Ecol. 
Monog. 26: 1-80. 



99 



RECREATIONAL IMPACTS IN THE SOUTHERN APPALACHIAN 
SPRUCE-FIR ECOSYSTEM 

Paul Richard Saunders 

Abstract . --Research in the Southern Appalachian spruce- 
fir forest ecosystem has shown forests are damaged by fire and 
windthrow; recreation has led to the introduction of exotic 
species and reduction of species cover and diversity, and 
effects of mule-logging on forest regeneration, floristics, and 
vegetation are minimal. Areas for research in Great Smoky 
Mountains National Park include the impacts of firewood gather- 
ing, windthrows at shelters and campsites, effect of diseases 
on tree vigor, recovery of balsam woolly aphid infested recrea- 
tion sites, soil erosion at recreation sites, reduction and 
rehabilitation of illegal campsites, and water quality monitor- 
ing and protection. 

Additional keywords : Backcountry use, dispersed recreation, 
wilderness. 

INTRODUCTION 

Southern Appalachian Mountain red spruce-Fraser fir ( Picea rubens - 
Abies fraseri ) forests (scientific nomenclature for vascular flora follows 
Radford, et al_. 1968) are a small disjunct, remnant ecosystem located above 
1670 meters on the higher mountain peaks of eastern Tennessee, western 
North Carolina and southwestern Virginia (see figure 1). While the area 
ranges from Mt. Rogers on the north to the Balsam Mountains on the south, 
most of the discussion will focus on the Great Smoky Mountains. 

Primarily as a result of logging followed by slash and successive 
fires, these forests have been reduced over 50 percent from 13,875 hectares 
of spruce-fir and 402ha of spruce to 6831ha of spruce-fir and 50ha of 
spruce (see table 1). Much of the area currently mapped as spruce-fir or 
spruce is not dominated by closed canopy forests. 

Recreation 

Today, recreation activities such as backpacking, nature walks, 
picnicking, photography and driving for pleasure are the principal uses of 
the remaining spruce-fir forests. With the exception of the Plott Balsam 
and Grandfather Mountains, most of the spruce-fir zone is in federal or 
state ownership. Portions of privately owned Grandfather Mountain are 
developed for tourists, where approximately 250,000 persons annually pay to 
see the exhibits and view from atop Grandfather Mountain (Steve Hart, 
personal communication, 1976). Except for the narrow corridor of the Blue 



Associate Professor of Wildland Recreation Management, Department of 
Forest and Range Management, Washington State University, Pullman, Washing' 
ton, 99164-6410. This is Scientific Paper 6627, Agriculture Research 
Center, Washington State University, Project 0596. 



100 



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101 



Table 1. Extent of the Southern Appalachian spruce and spruce-fir forests prior to and 
after logging. Area is in hectares. 





probable 


current 


iy 




Location 


past 


spruce- 


fir 


% of 




extent 


or spruce 


change 


Spruce-Fir Forests 










Great Smoky Mountains 


6013 


3665 




-39.0 


Plott Balsam Mountains 


662 


193 




-78.9 


Balsam Mountains (N.C.) 


3127 


614 




-80.4 


Black Mountains 


2524 


1457 




-42.3 


Roan Mountain 


896 


355 




-60.4 


Grandfather Mountain 


247 


220 




-10.2 


Mt . Rogers 


406 


326 




-19.7 



Subtotal 



13,875 



6831 



-50.8 



Spruce Forests 
Beech Mountain 
Elk Knob 

Grandmother Mountain 
Great Craggy Mountains 
Sampson Peak 
Unaka Mountain 
Whitetop Mountain 

Subtotal 

Total 



1 


0.1 


79 


- 


13 


5 


200 


10 


15 


- 


59 


- 


35 


35 


402 


50.1 


14,277 


6881.1 



-90.0 
-100.0 
-61.5 
-95.0 
■100.0 
-100.0 



-87.5 



-51. 



Ridge Parkway, there are no public recreation areas in the Plott Balsam 
Mountains. The only lodge or hotel remaining in operation within this 
ecosystem is Mt. Le Conte Lodge, a private concession, accessible only by 
foot or horse, on Mt. Le Conte in Great Smoky Mountains National Park. 

Mt. Mitchell State Park is accessible to the public only from the 
Blue Ridge Parkway, or the steep Commissary Ridge - Mount Mitchell Trail 
which originates 9 kilometers east of the park at 915 meters. The princi- 
pal attraction is the view from the tower atop Mount Mitchell (2038 
meters), the highest peak east of the Black Hills and Rocky Mountains. 
Annual visitation is slightly over a quarter million visitors who partici- 
pate in activities such as hiking, camping, picnicking and photography. 

The only spruce-fir area under jurisdiction of the U.S. Forest 
Service (USFS) where visitor use is monitored is Shining Rock Wilderness 
Area in Pisgah National Forest. Annual visitation to the 5425 hectare area 
is over a quarter million visitor days per year (one visitor day is any 
combination of people and times equal to 12 hours). The mean use of 47.4 



102 



visitor days per hectare makes it one of the most heavily used wilderness 
in the country. The USFS also has jurisdiction over spruce-fir areas near 
the wilderness, Mt. Rogers in the Balsam Mountains of Virginia, Roan 
Mountain, and most of the Black Mountains north of Mt. Mitchell State Park. 

The National Park Service (NPS) administers Great Smoky Mountains 
National Park (GSMNP) and the Blue Ridge Parkway (BRP) which passes near or 
through all spruce-fir areas (see figure 1) except Roan Mountain, Mount 
Rogers and Whitetop Mountain. Annual visitation along this 751 km roadway 
from GSMNP to Shennandoah National Park exceeds eleven million people. 

Over half of the remaining spruce-fir forests are within GSMNP, most 
of them virgin. The spruce-fir zone in the park accounts for 1.8 percent 
of the park area, yet has 10.8 percent (129 kilometers) of park trail 
distance, receiving approximately two-thirds of park day hikers (186,000 
visitors) and about 15 percent of overnight backcountry use (15,000 visi- 
tors) annually. Nearly half of the 113 kilometer Appalachian Trail within 
GSMNP lies within the spruce-fir zone. This is a popular trail because of 
its system of shelters, and its key location, thus about half of the 
backpackers (50,000) hike through spruce-fir forests annually. Adding to 
this area's high use is the paved Clingman's Dome trail with several 
hundred thousand annual visitors. 

Balsam Wool ly Aphid 

The balsam woolly aphid ( Adelges picea Ratzenburg) is an insect 
introduced into this country from Europe prior to 1908. It attacks all 
true firs or Abies , of which Fraser fir is the most seriously infested of 
the nine North American species (Mitchell 1966). The aphid was first 
discovered on Mt. Mitchell in 1957 (Speers 1958). By 1962 it had spread to 
Roan Mountain and in 1963 was detected in Great Smoky Mountains and on 
Grandfather Mountain (Amman and Speers 1965). Today all southern spruce- 
fir areas are infested with the balsam woolly aphid, some have suffered 
heavy losses. 

METHODS 

The field research on which this discussion is based was conducted in 
all spruce-fir areas and the all-spruce forest on Whitetop Mountains from 
1975 through 1982. Study was also made of mountains with planted spruce or 
fir; areas with historical (but not always accurate) accounts of past 
spruce or spruce-fir forests (Ayres and Ashe 1902a, 1902b, and 1905; Holmes 
1911; Pinchot 1897); and areas of sufficient elevation which currently, and 
perhaps historically, lack the fir component. All virgin, second-growth, 
logged, and balsam woolly aphid infested forests were sampled using a 
series of random 10x10 meter quadrats to provide baseline data on virgin 
and disturbed spruce-fir forest canopies and understories. A 2x2 meter 
nested quadrat was used to sample understory vegetation strata in the (1) 
ground layer - less than 5 centimeters tall, (2) herb layer - all other 
nonwoody herbs, and (3) shrub layer - all shrubs and trees less than 2.5cm 
dbh regardless of height. 

All recreation sites (hiking and nature trails, overnight campsites, 
overnight shelters and picnic areas) were sampled using a set of 3 meter 

103 



wide transects beginning in the center of the trail or campsite, or at the 
edge of the shelter or picnic table and of sufficient length (10-75 meters) 
to terminate within the forest. Percent cover was measured for each 
species at one-quarter or one-half meter intervals in the three vegetation 
strata. Overstory basal area was also measured. A spruce-fir and an 
all-spruce wind throw were sampled using the transect procedure. Sampling 
was designed to permit comparison of species presence and cover for all 
possible natural and human disturbances whether using plots or transects. 
To prevent additional complications, sampling was not done in human dis- 
turbed areas that had also been heavily infested by the balsam woolly 
aphid. 

RESULTS 

Transects used to measure the recreation disturbances were of differ- 
ent lengths, therefore the transects were divided into four vegetation 
zones to permit comparisons between disturbance types. The spatial loca- 
tion of the four zones for each type of disturbance is shown in Figure 2. 

The bare vegetation zone was always the site of the disturbance, 
being devoid of all but protected pockets of vegetation, generally lacking 
a litter layer, or containing a mosaic of bare soil and forest litter. 

The disturbed vegetation zone was located beyond from the bare 

vegetation zone and was also actively used for recreation. The disturbed 

zone was dominated by a forest litter layer and often contained plant 
species more resistant to human trampling. 

The transition vegetation zone was adjacent and beyond the disturbed 
zone and was used for recreation but withless intensity than the disturbed 
or bare zones. This zone contained a variety of herbs, shrubs, and trees 
with briars and tree reproduction the most important feature. 

The forest vegetation zone was farthest from the recreation distur- 
bance. It was infrequently entered by man, and was either virgin or 
second-growth stands. 

Windthrows showed all but the bare vegetation zone and were infre- 
quently entered by man, being almost impenetrable for recreation or samp- 
ling. However, they provide a comparison of natural disturbance and 
recovery against which human disturbance and recovery can be compared. 
Both windthrows, one of natural origin (Mt. Mitchell) and one of man-made 
origin in an all-spruce forest (Whitetop Mt.) are shown separately in 
Figure 2. The two windthrows are quite similar as neither has a bare 
vegetation zone. In comparison, all recreation disturbances have a bare 
zone radius of nearly 1 meter for trails, to 4 meters at picnic areas, 7 
meters at campsites and 8 meters at shelters. Trails represent a narrow 
corridor of disturbance, whereas picnic areas, campsites and shelters are 
much larger disturbances, with shelter creating a disturbance and canopy 
opening at least as large as windthrows. 

In order to better understand species response to disturbance, 
species response categories were defined using the vegetation zones. 
Categories were based on where each species had its highest mean cover and 

104 



Figure 2. Location of the four vegetation zones in the disturbances sampled 
with transects. Distance is from the center of the disturbance. 
B=bare vegetation zone, D=disturbed vegetation zone, T=transition 
vegetation zone, and F=forest vegetation zone. 



Type of 
Disturbance 



Whitetop Mt. 
Windthrow 



Mt. Mitchell 
Windthrow 



Shelters B | ID | T | 



Campsites B | D | T | F 



Picnic Areas 



I D I T I 



Trai Is 



iillL 



fill — i — | i i i i t i i i i | — i i i i i i « i « \ 

5 10 15 20 25 

Distance in Meters 



105 



other zones in which the species was present. The eight categories were 
(1) only in the forest zone, (2) only in the transition zone, (3) only in 
the disturbed and bare zone, (4) highest in the disturbed zone but also in 
the transition zone, (5) highest in the transition zone but also in the 
forest zone, (6) highest in the forest zone but also in the transition 
zone, (7) uniformly found in all zones, and (8) an irregular distribution 
or in all zones. Examination of the data found no species had a uniform 
distribution (#7), thus only seven response categories were found in the 
field. 

Species most sensitive to disturbances such as trampling, soil 
compaction, increased sunlight, greater temperature fluctuations, and other 
microenvironmental changes should be farthest from the disturbance or only 
in the forest zone. Species least effected by these disturbances would be 
in disturbed and bare zones. Exotic or nonnative species were frequent in 
these zones. Every species was not found in the same response category at 
each recreation or windthrow disturbance, thus discussion is based on 
average response for each species as shown in Table 2. 

Species found only in the forest zone occur primarily in the spruce- 
fir forest community (Ramseur 1960). Species listed in Table 2 were found 
near trails or smaller, less used campsites, but not near the larger 
disturbances. The species are not especially common or of higher cover in 
virgin or second-growth stands. They are assumed to be most sensitive to 
human and other disturbances. 

Only transition zone species do best in partial to full sunlight 
where trampling is minimal. The exotic Festuca spp. primarily F_. rubra , 
was present due to recent seeding along a nature trail. Its survivability 
in this environment remains to be seen. Diervilla sessilifolia is the most 
prevalent transition zone species at the Mt. Le Conte Lodge, GSMNP. 

Nearly all of the disturbed and bare zone only species were exotics, 
introduced at shelters, campsites, and picnic areas through direct seeding 
by managers, on boot soles of recreationists, and in horse droppings and 
horse feed horsepackers are required to carry. These species occurred at 
the most intensively used and disturbed sites studied, and are the same 
species frequenting roadsides, yards, and fields. The only tree reproduc- 
tion species listed was B_. papyri f era var. cordifol ia , found in the dis- 
turbed zone of the spruce-fir windthrow. It is an important tree in the 
regeneration of natural windthrows and burned areas, through few saplings 
survive to become mature trees (McLeod 1977, Sprugel 1974). 

The fourth category includes species with their highest cover in the 
disturbed and transition zones. Most are exotics introduced to the recrea- 
tion sites. The native Houstonia serpyl 1 ifol ia occurs where trampling is 
minimal along trail edges in both spruce-fir and hardwood forests. Rubus 
igaeus var. canadensis was found in both windthrows and picnic areas. Its 
seed longevity, possibly sixty-five or more years (Harrington 1972), makes 
it an important component of reestablishing the 50-75 year Southern Appa- 
lachian spruce-fir windthrow cycle. 



106 



Table 2. Species response to recreation and windthrow disturbance using seven response 

categories and ground/herb, shrub, and tree reproduction strata. Response class 
with highest cover is listed first. Exotic species are denoted by an asterisk (*) 
and species found only in windthrows by a(w). 



Response Class 



Ground/Herb 



Species by Strata 
Shrub 



Tree Reproduction 



Forest Zone Only 



Transition Zone 
Only 



Disturbed and 
Bare Zone Only 



Disturbed and 
Transition Zones 



Lycopidium lucidulum 

Asplenium montanum 

Poly podium virginianum 
Carex communis 
Veratrum viride 
Uvularia perfoliata 
Streptopus roseus 
Mediola virginiana 
Trillium erectum 
T. undulatum 
Circaea alpina 
Diphylleia cyomsa 
Monotropa unif lora 
Galax aphylla 
Stachs clingmanii 

* Festuca spp. 
Stellaria pubera 
Fragaria virginiana 
Hypericum mitchellianum 
Viola rotundifolia 
Eupatorium rogosum 

* Achillea millefolium 

* Poa spp. 

Carex aestivalis 

Smilax herbacea 
* Polygonum coccineum 

P. cilinode 
* Ranunculus acris 
* Taraxacum officinale 

* Poa annua 
P. alsodes 

*P. pratensis 

* Stellaria graminae 

* Trifolium repens 

* Plantago lanceolata 
Gallium trif lorum 
Houstonia serpyllifolia 



Viburnum cassinoides Amelanchier arborea 

var. laevis 
Illex ambigua var. 
montana 



Diervilla sessilifolia 
Vaccinium corymbosum 



w Betula papyrifera var. 
cordifolia 



Rubus idaeus var, 
canadensis 



107 



Table 2. Cont'd. 







Species by Strata 




Response Class 


Ground/Herb 


Shrub 


Tree Reproduction 


Transition and 


Athyrium asplenoides 


Ribes rotundifolia 


Abies fraseri 


Forest Zones 


Dryopteris campyloptera 


Rubus canadensis 


Picea rubens 




Carex debilis 


Menziesia pilosa 


Sorbus americana 




C. normal is 


Vaccinium 






C. brunnescens 


erythrocarpum 






Cimicifuga americana 


Viburnum alnifolium 






Podophyllum peltatum 








Saxifraga michauxii 








Viola macloskeyi var. 








pallens 








Angelica triquinata 








Aster acuminatus 








A. divaricatus var. 








chlorolepis 






Forest and 


Bryophytes 


Rhododendron 


Fagus grandifolia 


Transition Zone 


Carex intumescens 
Clintonia borealis 
Claytonia caroliniana 
Oxalis acetosella 
Solidago glomerata 


catawbiense 




Irregular 


Glyceria melicaria 


Ribes glandulosum 


Betula lutea 


Distribution 


Cinna latifolia 


Sorbus melanocarpa 


Prunus pensylvanica 




Carex spp. 


Sambucus pubens 


Acer spicatum 




Arisaema triphyllum 




A. saccharum 




Luzula acuminata 




Cornus alternifolia 




Maianthemum canadense 








Erythronium americanum 








Laportea canadensis 








Cardamine clematitis 








Impatiens spp. 








Viola spp. 








Cuscuta rostrata 








Monorda didyma 








Chelone lyoni 








Rudbeckia lacinata 








Senecio rugelia 







108 



The fifth category of species had their highest cover in the transi- 
tion zone, but continued with fairly high cover into the forest zone. When 
present in the bare or disturbed zone they were in well protected areas, 
such as next to the shelter or among tree roots. Many of these are shrub 
species, however spruce-fir forests usually do not have a well developed 
shrub stratum unless there has been windthrow, dying of canopy trees, or 
balsam woolly aphid infestation. Shrubs and tree reproduction occurred in 
a ring at the edge of the disturbance, an area not usually entered by 
recreationists. 

The sixth category of species had their highest cover in the forest 
zone, had considerable cover in the transition zone, and were rarely 
present in the disturbed zone. These shade tolerant species are not 
resistant to trampling. Combining the species in this and the previous 
category accounts for a majority of the typical Southern Appalachian 
spruce-fir forest species (Oosting and Billings 1951, Ramseur 1960, 
Saunders 1979, Schwarzkopf 1974, Whittaker 1956). 

The final category of species had an irregular distribution or were 
present in all vegetation zones, but were not prevalent in one zone or 
lacked sufficient data for their preferred location to be ascertained. 
None of these species are exotics and none, with one exception, are regard- 
ed as primarily spruce-fir forest species. The exception, Senecio rugelia , 
is principally a spruce-fir forest species and endemic to the Great Smoky 
Mountains. It occurred in the forest zone and transition zone at shelters 
and along trails, but did not do well when trampled. Prunus pensyl vanica , 
like Rubus idaeus var. canadensis is a disturbance species capable of 
revegetating severe disturbances such as fire and logging, but it is not 
common in windthrows. Its presence is dependent upon a mineral seedbed, 
and a seed source or buried seed longevity. Once established the saplings 
survive trampling. 

DISCUSSION 

This discussion of spruce-fir ecosystem management will first address 
what is known about spurce-fir forests and dispersed recreation and second- 
ly, identify recreation impacts that are not well known and how they might 
be studied. 

Known Impacts 

The literature (Brown 1941, Davis 1930, Korstian 1937) and recent 
research (Saunders, et a]_. 1981 and 1983) show fire to be a serious hazard 
in these forests. While there have been some dry years, annual precipita- 
tion of 150-220 centimeters usually is evenly distributed throughout the 
year, (Hardy and Hardy 1971, Data Services Branch 1976), making lightning 
fires a rarity (Bardens and Woods 1973). The major destructive fires were 
man-caused and followed large scale clearcut logging and improper slash 
disposal. Only one campfire which burned out of control caused much damage 
(Saunders, et al_. 1983). It burned one hectare and like other fire sites, 
has been slow to recover, probably due to destruction and erosion of the 
highly organic soils. 



109 



Spruce-fir forests are inherently susceptible to windthrow, especial- 
ly on exposed sites or when the canopy is opened. Soils are generally 
30-60 centimeters thick over bedrock (McCracken, e_t al_. 1962, Wolfe 1967). 
Both spurce and fir are shallow rooted trees. Most windthrow occurs in 
mature stands during high winds (95-300 kilometers per hour) in February, 
March and April when thawed soils permit trees to be easily blown down. 
Older firs are susceptible to bole breakage during high winds due to rotten 
or hollow boles. There is evidence of a growing windthrow at the Mt. 
Collins Shelter, GSMNP, in a stand of 200+ year old spruce. Clearing for 
construction of the shelter in 1960 created an opening in the forest 
canopy. 

Exotic species are present at the more heavily used recreation sites, 
or where managers have attempted seeding nonnative (exotic) plant mater- 
ials. To date, exotics have not been found within the forest, presumably 
because they compete best in the open bare and disturbed zones and poorly 
in the denser shaded transition and forest zones. The most important 
vector of exotics may be horses. At non-GSMNP spruce-fir recreation sites 
where horses rarely if ever are present, exotics were absent. Using 
sterile horse feed or prohibiting horses may help keep these species out of 
other recreation sites. The major problems with the introduced species is 
their ability to out compete native spruce-fir species, creating potential 
for escape into this ecosystem, and their disruption of site visual appeal. 

As shown in Table 2, most of the common spurce-fir species respond to 
recreation impacts, primarily trampling and the resultant soil compaction 
in a fairly predictable manner. Other factors influencing species response 
include increased sunlight in forest openings and increased microclimatic 
fluctuations and temperature and moisture extremes. None of the native 
species are well adopted to this kind of impact, thus the large bare and 
disturbed zones surrounding shelters (707 square kilometers) and campsites 
(314 sq km), and the presence of exotic species. Given reduced vegetation 
cover and increased soil erosion, openings and impact sites should be kept 
as small as possible. Not only will this improve site vegetation and soil 
conditions, but also the site aesthetics. 

A firewood logging operation has been conducted to supply the Mt. Le 
Conte Lodge, GSMNP, since its origin as a tent camp some 75 years ago. 
Logging was halted in July 1976. Examination of this mule-logged area 
found it to have a floristic composition similar to that of virgin stands, 
although fewer species were present and species cover values were differ- 
ent. The mule-logged stand contained more shrub cover and denser tree 
reproduction. Soil erosion appeared minimal because of the narrow skid 
trails and absence of roads. Site recovery was excellent, especially when 
compared to recent machine-logged stands and a closed canopy spruce-fir 
forest should result. 

Unknown Impacts and Monitoring 

One spruce-fir recreation problem for which there is no answer is the 
impact of firewood gatherings on vegetation trampling, nutrient cycling, 
and careless or deliberate cutting of live trees and saplings. There are 
hikers who persist in using fires for cooking purposes, leading them to cut 
live trees because they were conveniently close. The campfire impact 

110 



should be studied using an available fuels and vegetation comparison 
between areas with and without wood gathering. 

Windthrows are a natural disturbance mechanism in spruce-fir forests, 
but they also occur when man opens the forest canopy. Long term study is 
needed at several GSMNP shelters, especially Mt. Collins and Tricorner 
Knob, to determine if canopy openings will stabilize or continue enlarging. 
Study is also needed on how these areas which receive recreation use, will 
recover relative to other natural, undisturbed windthrows. 

Fungi and disease are known to weaken the trunks of fir, and probably 
spruce. Injury of these and other thin barked trees from axes, and scuff- 
ing of roots by hikers and horses provides an easy entrance for diseases. 
Research has not been done on what diseases are present, individual species 
resistance, and what portion of trees at recreation sites compared to 
undisturbed sites are infected. 

The balsam woolly aphid infestation has spread widely, especially in 
GSMNP, since this recreation impact study began nearly a decade ago. As a 
result several recreation sites have lost and more are losing their fir 
canopy. Since use is still occurring at these sites, questions needing 
answers are how well will these sites recover, and will the reduced canopy 
and increased sunlight permit exotic species to invade the spruce-fir 
forest. Woody exotics are a problem in GSMNP in lower elevation succes- 
sional deciduous forests (Baron, et al_. 1975). 

Soil erosion is a problem with the thin, organic soils on these often 
steep sites. The rate and amount of soil erosion at recreation sites has 
not been quantified. Soil cores from some shelters show a complete loss of 
the A horizon. Some trails on ridge faces have become major drainage ways, 
eroding to depths of a meter or more. Many trail sections have exposed 
tree roots (an entry for disease) and exposed bedrock or C horizons. This 
research should focus not only on what soil erosion is occurring, but also 
on how to control it. 

Illegal campsites are a problem along all trails, especially the 
Appalachian Trail in GSMNP. The backcountry permit system was begun over a 
decade ago to eliminate this problem by designating overnight sites and 
controlling the location and number of people at all backcountry overnight 
campsites and shelters. Late visitors to the park often do not obtain a 
permit and other users simply ignore the posted regulations at all trail - 
heads. Such users either cause overcrowding at legal sites, or they as 
well as users with permits go to illegal sites to avoid crowded conditions. 
Most illegal campsites are small, but their presence is obvious and a 
signal to other backpackers of a possible campsite. Elimination and 
rehabilitation of these sites may discourage use and prevent some trail 
sections from looking like a continuous series of campsites. In addition, 
an education program for all GSMNP backcountry users explaining the reasons 
for the permit system may help reduce this problem. 

All backcountry users and their livestock need to eliminate body 
wastes periodically. The location and methods of waste disposal is 
critical to the health of all users and the environment. Recent research 



ill 



(Temple, et a_l_. 1980) has shown that the recommended method, shallow burial 
in holes 5-20 cm deep, does not kill bacteria even after 3 years. All 
overnight sites are located near springs, which are not common in the 
spruce-fir forest. Water quality needs to be continually monitored at 
these sites as well as studies undertaken to determine the safest means of 
waste disposed by both humans and livestock. 

CONCLUSIONS 

Research in the Southern Appalachian spruce-fir forest ecosystem has 
shown that (1) the forests and soils are easily damaged by fire, (2) wind- 
throw is a natural perturbation which also occurs when the forest canopy is 
opened by man, (3) exotic species are prevalent in recreation disturbed 
sites, (4) native spruce-fir species cover and diversity is severely 
reduced by recreation activity into four distinguishable vegetation zones, 
and (5) mule-logging does not damage the soil or reduce species richness 
nearly as much as recent machine-logging. Research needs associated with 
dispersed recreation in this ecosystem are (1) the impact of firewood 
gathering on vegetation and nutrient cycling, (2) if canopy openings for 
shelters and campsites will stabilize or expand as a result of subsequent 
windthrow, (3) effect of tree diseases introduced by root and trunk injury 
on individual tree and canopy health, (4) effect of continued recreation 
use on recovery of balsam woolly aphid infested stands, (5) amount of soil 
erosion at recreation sites and along trails, (6) reduction and rehabili- 
tation of illegal campsites, and (7) monitoring water quality and devel- 
oping safe means of human and animal waste disposal. Research and manage- 
ment problems were not prioritized, but the issue of water quality is 
probably the most important to the users of these forests. 

LITERATURE CITED 

Amman, G. D. and C. F. Speers. 1965. Balsam woolly aphid in the Southern 
Appalachians. Journal of Forestry. 63( 1 ) : 18-20. 

Ayres, H.B. and W. W. Ashe. 1902. Description of the Southern Appalachian 
forests by river basin. j_n U. S. Department of Agriculture. Message 
from the President of the United States. Government Printing Office. 
Washington, D.C. p. 69-92. 

. 1902. Forests and forest conditions in the Southern Appala- 



chians. j_n U. S. Department of Agriculture. Message from the President 
of the United States. Government Printing Office. Washington, D.C. 
p. 45-60. 

1905. The Southern Appalachian forests. U. S. Geological 



Survey. Washington, D.C. Professional Paper 37. 291 p, 

Barden, L. S. and F. W. Woods. 1973. Characteristics of lightning fires 
in the Southern Appalachian forests. Proceedings of the Annual Tall 
Timbers Fire Ecology Conference. 13:345-361. 



112 



Baron, J., C. Dombrowski, and S. P. Bratton. 1975. The status of five 
exotic woody plants in the Tennessee District, Great Smoky Mountains 
National Park. U. S. Department of Interior, National Park Service, 
Southeast Region, Atlanta. Research/Resources Management Report No. 2. 
26 p. 

Brown, D. M. 1941. Vegetation of Roan Mountains: a phytosociological and 
successional study. Ecological Monographs. 11(1): 61-97 . 

Data Services Branch. 1976. Precipitation in Tennessee River basin: 
annual 1976. Tennessee Valley Authority. Division of Water Management. 
Knoxville. 15 p. 

Davis, J. H., Jr. 1930. Vegetation of the Black Mountains of North 
Carolina: an ecological study. Journal of the Elisha Mitchell Scien- 
tific Society. 45(2) :291-318. 

Hardy, A. V. and J. D. Hardy. 1971. Weather and climate in North 
Carolina. North Carolina Agricultural Experiment Station. Raleigh. 
Bulletin 396 (revised). 48 p. 

Harrington, J. F. 1972. Seed storage and longevity. j_n Kozlowski, T. T. 
(ed). Seed Biology. Volume 3. Academic Press. New York. p. 145-245. 

Holmes, J. S. 1911. Forest conditions in western North Carolina. North 
Carolina Geologic and Economic Survey. Chapel Hill. Bulletin No. 23. 

Ill p. 

Korstian, C. F. 1937. Perpetuation of spruce on cut-over and burned lands 
in the higher southern Appalachian Mountains. Ecological Monographs. 
7(1) :125-167. 

McCracken, R. J., R. E. Shanks, and E. E. C. Clebsch. 1962. Soil morph- 
ology and genesis at higher elevations of the Great Smoky Mountains. 
Soil Science Society of America Proceedings. 26(4) :384-388. 

McLeod, D. 1977. Paperbirch ( Betula papyrifera var. cord if ol ia (Regal) 
Fernald) in the Black Mountains of North Carolina, jut. Proceedings of 
the Third Annual Meeting on Scientific Research in the National Parks of 
the Uplands Area of the Southeast Region. Gatlinburg. p. 36. 
(abstract) . 

Mitchell, R. G. 1966. Infestation characteristics of the balsam woolly 
aphid in the Pacific Northwest. USDA. Forest Service. Pacific North- 
west Forest and Range Experiment Station. Portland. Research Paper 
PNW-35. 18 p. 

Oosting, H. J. and W. D. Billings. 1951. A comparison of virgin spruce- 
fir forests in the northern and southern Appalachian system. Ecology. 
32(1) :84-103. 

Pinchot, G. 1897. Timber trees and forests of North Carolina. North 
Carolina Geological Survey. Raleigh. Bulletin No. 6. 227 p. 

113 



Radford, A. E., H. E. Ahles, and C. R. Bell. 1968. Manual of the vascular 
flora of the Carol inas. University of North Carolina Press. Chapel 
Hill. 1183 p. 

Ramseur, G. S. 1960. The vascular flora of high mountain communities of 
the Southern Appalachians. Journal of the Elisha Mitchell Scientific 
Society. 76(1) :82-112. 

Saunders, P. R. 1979. Vegetational impact of human disturbance on the 
spruce-fir forests of the Southern Appalachian Mountains. Ph.D. Disser- 
tation. Duke University, Durham, North Carolina. 177 p. 

, G. S. Ramseur, and G. A. Smathers. 1981. An ecological investi- 



gation of a spruce-fir burn in the Plott Balsam Mountains, North 
Carolina. U. S. Department of Interior, National Park Service, Southeast 
Region, Atlanta. Research/Resources Management Report No. 48. 16 p. 

, G. A. Smathers and G. S. Ramseur. 1983. Secondary succession of 



a spruce-fir burn in the Plott Balsam Mountains, North Carolina. 
Castanea. 48(1) :41-47. 

Schwarzkopf, S. K. 1974. Comparative vegetation analysis of five spruce- 
fir areas in the Southern Appalachians. Honors Thesis. Furman Univer- 
sity. Greenville. 117 p. 

Speers, C. F. 1958. The balsam woolly aphid in the Southeast. Journal 
of Forestry. 56( 7 ): 515-516 . 

Sprugel , D. G. 1974. Natural disturbance and ecosystem response in wave- 
regenerated Abi_es_ bal_samea forests. Ph.D. Dissertation. Yale Univer- 
sity. New Haven. 287 p. 

Whittaker, R. H. 1956. Vegetation of the Great Smoky Mountains. Eco- 
logical Monographs. 26(1): 1-80. 

Wolfe, J. A. 1967. Forest soil characteristics as influenced by vegeta- 
tion and bedrock in the spruce-fir zone of the Great Smoky Mountains. 
Ph.D. Dissertation. University of Tennessee. Knoxville. 193 p. 



114 



PRE-PARK DISTURBANCE IN THE SPRUCE-FIR FORESTS 
OF GREAT SMOKY MOUNTAINS NATIONAL PARK 

Char lotte Py I e 

Abstract. The major pre-park disturbances in the spruce-fir zone of Great 
Smoky Mountains National Park were mechanized logging and logging slash 
fires. Estimates by previous authors of prelogging and postlogging spruce- 
fir areas in the Southern Appalachians as well as in the national park were 
reviewed. Area of spruce-fir extant in the park following logging was 
estimated by means of a dot grid laid over the "spruce" portions of the 
Miller vegetation type map of the park. Miller's "spruce" was analogous 
to what I have called "spruce-fir" for this analysis. Spruce-fir was 
broadly defined to include three cover types of the Society of American 
Foresters (red spruce-yellow birch, red spruce, and red spruce-Fraser fir) 
as well as spruce with a rhododendron understory and stands dominated by 
Fraser fir alone. Estimated spruce-fir area prior to logging was based 
on early maps and timber estimates found in the Park Archives. The 
difference in the prelogging total (17,910 hectares) of spruce-fir versus 
postlogging total (13,370 hectares) was attributed to destruction of 
habitat following fire. The possibility of additional loss of spruce due 
to failure of cut-over spruce to regenerate in stands that were originally 
a mixture of spruce and hardwoods was also discussed. 



INTRODUCTION 

The spruce-fir zone in Great Smoky Mountains National Park (GRSM) is 
found in the highest elevations in the park, along the North Carol ina/- 
Tennessee state line west from Cosby Knob to about Double Springs Gap. Major 
spruce-fir ridges extending from the state line are (I) from Tri-Corner Knob 
southeast to Big Cataloochee Knob and on in a southerly direction, as well as 
east to Mount Sterling; (2) from Mount Kephart out the Boulevard to Mount 
LeConte; and (3) Mingus Ridge. In addition, Raven Fork is unusual in the 
park, with spruce covered coves as well as ridges extending down to 4500 feet 
elevation and below throughout the watershed. An outlying population of 
spruce is found west of Double Springs along Miry Ridge. 

The major prepark disturbances in the spruce-fir zone were mechanized 
logging and slash fires. Prior to acquisition for the park, ownership of the 
spruce-fir zone was divided among several timber companies who sought spruce 
for lumber and pulp. This corporate ownership reflects the fact that, unlike 
other forest types in GRSM, the spruce-fir offered little to farmers and 
livestock herders; consequently, the type as a whole was little impacted by 
farming activities. Extremely limited use of the GRSM spruce-fir zone by 
stockholders (e.g., on Andrews Bald or Mount Sterling) is in contrast to the 
situation reported by Hopkins (1899) for West Virginia spruce-fir, where 
herders girdled trees and subsequently burned large areas for pasture. 
Hopkins discussed several other disturbances in the spruce vegetation of West 
Virginia. Of these disturbances (logging, fire, clearings, roads, commercial 
railroad construction, bark beetles, and windfalls), only logging and slash 
fires were important in GRSM during the prepark era. Although there do exist 



Biological Technician, Uplands Field Research Laboratory, Great Smoky 
Mountains National Park, Gatlinburg, Tennessee. 

115 



records of "blowdowns," disturbance to spruce-fir vegetation by windfall prior 
to park est ab i shment was insignificant in relation to the total area of this 
vegetation type. 

LOGGING HISTORY 

Because spruce is a high elevation species, and the high elevations of 
Great Smoky Mountains were quite inaccessible, the spruce-fir zone in GRSM 
was not affected by the early small-scale and technologically simple logging 
operations of local people. An example of the prevalent logging technology 
associated with early logging in GRSM was the use of horse teams in 
accessible hardwood coves to drag logs to a portable mill set up on the site, 
from which cut lumber was hauled by wagon to market. Fol lowing the 
development, in the early 1900s, of highly mechanized technology in logging 
as well as improved methods of wood processing, commercial corporations 
became interested in the remote spruce-fir zone of the Smokies (Lambert 
1958). These well financed outside operators built large mills and used 
mechanized skidders plus railroads to bring logs long distance to the mills 
(Lambert 1958). 

Loggers' demand for spruce was related to its physical properties — strong 
and lightweight wood and ability to be pulped by the sulfite process (which 
had been reintroduced into the United Statesin 1887; Panshin et al. 1962). The 
heyday of spruce cutting in GRSM was during the first World War, at which 
rime not only was the timber cut for pulp but also for wood to be used 
in aircraft construction. In 1918, Suncrest Lumber Company was receiving 
a U.S. government subsidy (in the form of 200 "army men") for extraction 
of spruce from Big Creek watershed (Hardwood Record 45:39, 8/25/18, located 
in GRSM Archives). At the end of World War I this aid was cut off. A 
million and a half board feet of spruce logswere left lying on the ground, 
signal inc the end of an operation that was no longer profitable (Lambert 
! 958 ) . The demand for spruce pulp was expected to be more or less continuous 
after the completion of a pulp and paper mill in 1905 in Canton, North Carolina 
(Champion Fibre Co. records, "Expect to Prove: History," located in GRSM 
archives). It was for this expected demand that Champion Fibre Co. in 
particular had acquired such a large reserve of spruce-fir forest in GRSM. 
However, before Champion and the other timber corporations were able to 
log all the spruce-fir zone, condemnation proceedings began for the proposed 
Great Smoky Mountains National Park. In conjunction with this, Champion's 
cutting of spruce in GRSM ceased in 1927 (Champion Fibre Co. records, 
"Expect to Prove: History"). 

SOURCES OF INFORMATION ON SPRUCE-FIR DISTURBANCE HISTORY 

Following condemnation, the timber companies were interested in getting 
a maximum price for their holdings. As a consequence, transcripts of 
the condemnation proceedings contain many differing opinions as to exactly 
the quantity and value of the timber that was left within a company's 
boundary. Furthermore, because concern was with how much, not where, 
testimony was often vague as to actual location of cut versus uncut areas. 
For the most part, rather than written records, the best parkwide source 
of information on logging impacts in the spruce-fir zone is a map made 
by Frank Miller, a National Park Service ( NPS ) forester in the 1930s. 
Miller's map shows vegetation types, including a "spruce" type plus 



116 



a "cut over" line and a "burned" designation. The cut-over line delineates 
logging that altered the area enough to present a fire danger different from 
the adjacent noncut-over tracts. Such logging is called "heavy cut" by- 
other anonymous map sources in the GRSM Archives. The boundaries of "cut 
over" or "heavy cut" do not include areas where a few big trees were 
selectively removed from a stand. 

A second source of mapped information on logging impacts in the spruce- 
fir is the type maps made in the 1930s by the Tennessee Valley Authority 
(TVA). For GRSM, the TVA generated vegetation type boundaries and stocking 
are based entirely on ocular estimation in contrast to Miller's types and 
stocking based on I /5-acre plots in addition to ocular estimation. 

A third vegetation typing method was employed by Chris Eagar of Uplands 
Field Research Laboratory, who made a parkwide set of spruce-fir type maps 
based on interpretation of recent aerial photographs (C. Eagar, unpublished 
maps, Uplands Field Research Laboratory,)- Areas of spruce-fir forest where 
effects of fire or logging could be recognized in the air photos were mapped. 

Although wri tteir records of spruce-fir distribution prior to and following 
logging were generally not site specific, certain references are useful in 
consideration of the probable original effects of logging on spruce-fir 
vegetation. Buckley (1859), Hopkins (1899), Whittaker (1956), and Saunders 
(1979) discussed general placement of a lower elevational boundary for 
spruce or the spruce-fir type. Ayres and Ashe (1902) discussed Southern 
Appalachian spruce in general terms and also (1905) gave watershed 
descriptions that included mention of percent spruce present. Korstian 
(1937) and AAinckler (1940) described problems with spruce regeneration 
following logging in the Southern Appalachians. Lambert's (1958) unpublished 
report available at GRSM library), although lacking in information mappable 
at the 1:24,000 scale, contains a detailed written compilation of information 
concerning logging operations specific to GRSM. Finally, the GRSM Archives 
houses a variety of documents representing most of the logging companies in 
operation at the time of park land acquisition. 

METHODS 

Location and areal measurements of spruce and/or fir vegetation types 
were based mainly on the maps described above. Air photos were superficially 
examined as a check on reasonableness of maps of current spruce-fir vegetation 
Because field work was beyond the scope of this present work, reliance was 
placed also on written records of estimates of total prelogging era spruce- 
fir acreage in certain watersheds. Use of historic estimates of spruce area 
allows for calculation of loss of area of the spruce forest type but does 
not confer knowledge concerning actual location of extirpated spruce beyond 
the major watershed unit. 

Because it was based on field plots and extensive field reconnaissance, 
the Miller map was used as the main source of information on existing 
spruce-fir in GRSM. A dot grid (64 dots per square inch) was used to 
estimate area after it was found that the uneven surface of the map was not 
conducive to planimetric estimates. A second dot grid estimate was made as 
a check of the first, and the small differences in the two were averaged to 
produce the final spruce-fir area estimate used for each watershed. Number 
of hectares total in each major watershed were taken from estimates of area 
based on the National Park Service Denver Service Center digitization of 

117 



watershed boundaries marked on 7-1/2 minute topographic sheets. 

To estimate spruce-fir area lost following logging, several methods 
were used, depending on watershed, history and available information. 
In the upper reaches of the Oconaluftee River, a small area believed to 
have been partially covered by spruce had been burned in 1925. The method 
used for this watershed started with derivation of expected extent of 
spruce forest type based on estimating the average elevation of spruce 
in the adjacent Bradley Fork watershed as shown on the Miller map. Bradley 
Fork was not logged at high elevation and has much the same general aspect, 
topography, and relief in relation to surrounding landforms as does the 
upper Oconaluftee River. In Bradley Fork, the average boundary of spruce 
was 4500 feet elevation on the the ridges and, in draws, 5350 feet. The 
difference in area of present spruce zone versus expected area was estimated 
with a dot grid placed over the Miller maps. Dots were counted between 
Miller's marked boundaries and the expected boundaries of 4500 feet on 
ridges and 5350 feet in draws. 

Although Bradley Fork was not logged at high elevations, in 1925 a 
large logging slash fire in the Oconaluftee River watershed overlapped 
into uncut spruce-fir in Bradley Fork as well as across the state line 
divide into the Middle Prong around Charlies Bunion. An arbitrary elevation 
of 4500 feet was taken for the original boundary of spruce on the widely 
convex ridge extending into the Middle Prong from Charlies Bunion. In 
Bradley Fork, the position of extant spruce on Richland Mountain (adjacent 
to the burned area) very near I y defined the prefire extent of spruce. 

Although Straight Fork and Bunches Creek were heavily logged, there 
were no major fires at high elevation. Therefore, as will be discussed 
later, no nonspruce areas were construed as having supported spruce-fir 
forests prior to logging. 

In contrast, in the Cataloochee watershed there was high elevation 
logging followed by fire. Both written records and maps give reason to 
believe that the burned area south of Mount Sterling Ridge now forested 
in hardwoods once supported spruce vegetation. In a letter to the North 
Carolina Park Commission dated December 7, 1929, J. F. Green and others 
wrote, "We followed most of the high line of railroad constructed by the 
Ravensford Lumber Company from Pin Oak Gap around to the head of Little 
Cataloochee, a distance of 18 miles. We found this line followed about 
the lower edge of the spruce belt... We find the spruce had been taken 
below the railroad for a distance of 1500 to 2000 ft and the hemlock left 
standing.... Also. ..this cut over land has since been burned over and 
everything destroyed." The catastrophic burn is documented on Miller's 
map. Based on the information contained in this letter, the boundary' 
of "spruce lands" from a sma I I scale prelogging era map in the GRSM archives 
(Uplands Lab Map Index No. 81) was transferred freehand to a USGS 1:2400 
scale topo sheet. This boundary corresponded very well to the old railroad 
grade shown on the current USGS map. Miller's fire boundaries extend 
some 1000 to 2000 feet farther downslope of this railroad grade, further 
corroborating Green's observations. 

In order to estimate area once covered by spruce vegetation in this 
part of the Cataloochee watershed, arbitrary prelogging boundaries were 
created based on the assumption that the railroad grade was indeed in 
the vicinity of the lower boundary of spruce and that the local pattern 
of spruce distribution included spruce fingers extending down ridges and 
hardwood inroads up draws. Additionally, based on the same map source 

118 



(map 81), an arbitrary boundary of prelogging spruce forest was created 
for a small area within the burn on Shanty Mountain, which is also in 
the Cataloochee watershed. Burned area on Shanty Mountain was estimated 
with a dot grid laid over a marked xeroxed copy of the Miller map. Area 
of burned spruce marked on the 1:24000 scale was estimated by taking the 
average of three planimetric determinations. 

In the other two GRSM watersheds where much of the spruce-fir vegetation 
type was destroyed by fire (Forney Creek and Big Creek), no attempt was 
made to reconstruct prelogging spruce boundaries due to the fact that 
no prelogging spruce-fir maps could be located. However, a general estimate 
of the area of spruce removed was made based on written records of prelogging 
spruce-fir acreage. The Big Creek watershed was one of the most extensively 
burned watersheds in the park. Its upper reaches are rather remote, and 
little was known about its prelogging vegetation. Ayres and Ashe (1905) 
did not even list spruce as a component of the vegetation, although Mount 
Guyot and Tri-Corner Knob, which are a part of the major mountain mass 
of spruce-fir zone in the Great Smoky Mountains, serve as boundaries of 
the watershed. It appears, however, that by 1911 the area was becoming 
better known. The October 1911 issue of American Lumberman contained 
an article that included: "It will require five switchbacks on some of 
the mountains in order to reach the spruce which is found above 4500 feet." 
Also in 1977, the Lemieux Brothers and Company (timber estimators) estimated 
that there were 4850 acres of spruce land in the Big Creek watershed. 
It is not clear whether this estimate includes what was then known as 
Upper Baxter Creek (now Sinking Creek). 

Given that little sign of past presence of spruce (other than the 
occasional spruce crown seen emerging from the numerous rhododendron thickets) 
is visible on current aerial photography, and that Miller in the 1930s 
typed very little area as spruce, one might conclude the reports of spruce 
in Big Creek were greatly exaggerated. If one takes Camel Gap on the 
North Carolina/Tennessee border as the easternmost boundary of continuous 
spruce-fir of the northern edge of the Big Creek watershed and uses, for 
the lower limit of spruce, a consistent 4500 feet contour around the watershed 
to the unlogged area near Mount Sterling, then the estimated total area 
of spruce-fir in Big Creek is considerably more than 4850 acres. However, 
if one hypothesizes a spruce boundary that falls as slow as 4500 feet 
on ridges and as high as 5500 feet in draws (a pattern similar to that 
in the unlogged Bradley Fork spruce-fir forest), then the total estimate 
of 4850 acres of spruce is within the realm of reason. Given that no 
better information was found, the Lemieux Brothers and Company estimate 
of 4850 acres ( ^ 1 963 hectares) was taken for the prelogging area occupied 
by spruce-f i r . 

Because the spruce-fir type remaining in the Big Creek watershed is 
small and in disjunct patches, it was not suited to areal estimates by 
dot grid on the 1:62500 scale. However, Miller's plot records (in the 
GRSM Archives) included area estimates made from a no longer available 
set of 1:24000 scale maps showing Miller's type boundaries. These estimates 
of cut-over and virgin spruce were used. The difference between Mi I ler's area 
estimate and the Lemieux Brothers and Company estimate was accepted as 
the amount of spruce-fir forest lost due to logging fires. This does not 
correspond mapwise to the area shown by Miller as burned in 1925. However, 
there are records in this watershed of earlier spruce-fir fires not recognized 
in Miller's mapping (e.g., Lambert 1958; Anonymous Lumbering Map made 
circa 1928-1930, Uplands Lab. Map Index No. 58, in GRSM archives). 

119 



Lambert (1958) reported that prior to logging by the Norwood Lumber Company, 
there was an estimated 30,000,000 board feet of spruce in the forney Creek 
watershed. He gives the average cut as l r ),000 board feet per acre. This work-, 
out to an original spruce-fir /one of 2000 acres ( % 809 hectares). Close 
examination of current air photos does not show a great abundance of spruce in 
the watershed. Proposed reasons are that spruce was decimated in the logging 
slash fires of the 1920s; or that Forney Creek, being on the westernmost edge of 
the spruce-fir zone in GRSAA and being more southwest-facing and less sheltered by 
surrounding landforms, may never have supported as much spruce-fir vegetation as 
other large spruce-fir-containing watersheds. For lack of better record, 809 
hectares was taken as the total spruce-fir area encountered by loggers. 

A final word on methods concerns the separate tallying of selectively cut 
areas. In most cases, selectively cut areas correspond to small areas designated 
"light cut" by Miller on the wilderness overlay he made in 1942 for his type map. 
However, in Forney Creek, Straight. Fork, and Cataloochee Creek, small areas 
designated virgin by Miller were treated by the author as selectively cut, based 
on field observation and corroborating evidence from air photos. 

RESULTS 

Of the 28 major watersheds in GRSAA, 17 have spruce-fir vegetation. In 
three of the watersheds, there were major logging slash fires which resulted in a 
loss of one-fourth of the spruce-fir area believed to have been found in the Great 
Smoky AAountains prior to logging. Prior to logging, it was estimated there were 
17,910 hectares of spruce-fir type. This is equal to 8.7 percent of the total 
area of the park. The area of spruce-fir extant fol lowing logging in the park 
was 13,370 hectares, or 6.5 percent of the total park area. Of the extant area, 
90 percent (12,100 hectares) was not logged. It should be pointed out that these 
12,100 hectares of unlogged forest represent only 68 percent of the area occupied 
by spruce-fir prior to logging and logging slash fires. Table I shows tabulations 
by watershed of spruce-fir type area. The "cut and burned" or "burned/no cut" 
area within certain watersheds is based on estimates outl.i-ned under "Methods" and 
represents areas believed to have been covered with spruce-fir prior to logging 
activities in GRSAA. The tabulations in Table 2 deal only with extant spruce-fir. 

Prior to logging in the park, spruce-fir was most important in the West 
Prong, Middle Prong, Big Creek, Cataloochee Creek, and Raven Fork watersheds. 
Fire fol lowing logging decimated the spruce-fir in Big Creek and Cataloochee 
Creek, removing 78 percent and 85 percent, respectively, of the spruce-fir 
vegetation. Slash fires were also important in Forney Creek, where the spruce-fir 
was reduced to 20 percent of its original area. In general, if a watershed was 
logged extensively, if burned. An exception was Bunches Creek, which, as far as 
the records show, did not have fire in its 280 hectares of extant but heavily cut 
spr uce-f i r . 

Today, over 45 percent of the extant spruce-fir in the park is in two 
watersheds. Raven Fork and the Middle Prong. Addition of the West Prong makes 
three of the 17 spruce-fir-containing watersheds in GRSM account for nearly 60 
percent of the spruce-fir. 



120 





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122 



DISCUSSION 

Both prelogging and postlogging area estimates of spruce-fir vegetation 
in the Southern Appalachians have produced widely differing sets of numbers 
as a result of widely differing sets of assumptions. A major source of 
variation is in the definition of "spruce-fir." For purposes of this 
paper, "spruce-fir" includes pure fir, spruce and fir mixed, pure spruce, 
spruce and hardwoods and/or hemlock, and spruce and rhododendron. Because 
spruce was a tree of commercial importance, there are more historical 
records of distribution of spruce forests than of the spruce-fir vegetation 
type i tse I f . 

Barring competitive interactions, the best forest site for spruce 
is the sandy loams found on moist but well-drained slopes and benches 
(Korsfian 1937). These rich moist upper cove positions are generally 
dominated by northern hardwoods vegetation in the Great Smoky Mountains. 
Holmes (1911) described the spruce forests in Western North Carolina as 
chiefly spruce and balsam with a small percentage of yellow birch and 
other hardwoods. While Holmes agreed that spruce individuals reach their 
best development on richer sites, he said that red spruce "is confined 
almost entirely to the spruce forest of higher mountains, though a few 
straggling trees descend into the hardwood forest below." In contrast, 
with respect to the distribution of spruce, Miller (Brief narrative 
descriptions of the vegetative types in Great Smoky Mountains National 
Park, 1938, unpublished) as well as Schofield (I960) described the transition 
in the spruce-fir zone between pure conifers and pure hardwoods as gradual 
in undisturbed forests. 

It appears that Holmes' impression of spruce forest was one based 
on looking from a great distance at the patterns in the landscape. From 
such a viewpoint, the boundary between broad bands of coniferous versus 
hardwood forest appears well defined, and the "few straggling trees" 
descending into the hardwood belt are those trees on ridgetops, where 
the elevational boundary of the spruce type may drop 500 feet below that 
of the general boundary. 

To the observer standing in the forests of GRSM, "a few straggling 
trees" describes the pattern of individual spruce trees as the spruce 
type gives way gradually to the northern hardwood type. Given that, from 
a closeup point of view, the transition between spruce-fir and hardwoods 
is gradual (except, as Schofield (I960) points out, where there was logging 
followed by fire), in order to map spruce-fir vegetation one needs a 
definition that addresses al lowable extent of species other than spruce 
or fir. The Society of American Foresters ( SAF ) defines cover types by 
the following rules: (I) names are given according to which species (of 
the dominant and codominant stems only) are numerically predominant in 
a forest, and (2) the species which appear in the type name should form 
50 percent or more of the forest composition, with the most numerically 
important species listed first (SAF 1954). Spruce-fir SAF forest cover 
types applicable in the Southern Appalachians are red spruce-yellow birch 
(which can be associated with Fraser fir, yellow buckeye, beech, sugar 
maple, and mountain-ash); red spruce (in which red spruce can be pure 
or predominant and associated with yellow birch, sugar maple, red maple, 
hemlock, white ash, mountain-ash, Fraser fir, and yellow buckeye); and 
red spruce-Fraser fir (in which red spruce and Fraser fir can be in pure 
association or predominant and associated at the lower altitudinal portions 
of the type with hemlock, yellow birch, beech, sugar maple, yellow buckeye, 
mountain-ash, and hawthorn). 

123 



Spruce types such as those detined by SAF allow one to type a forest stand 
in which one has counted the trees. It says nothing about general patterns on 
the landscape. However, most areal estimates of extent of widespread forest 
cover types have been based on perception of some pattern in the landscape 
rather than on field plots. In general, for spruce-fir in the Southern 
Appalachians, the pattern has been defined via the lower elevational limit of 
spruce, due to the fact that spruce-fir is the uppermost vegetational belt in 
the region, with spruce having lower elevational limits than fir. 

Elevational placement of the lower limit of spruce-fir depends on the 
definition of spruce-fir vegetation and the latitude of the observer. 
Frothingham (1931) generalized the spruce forest as "found at altitudes of 
over 4500 feet in the mountains of North Carolina, Tennessee, and Virginia, ana 
at altitudes of over 3500 feet in West Virginia." Because early records of 
spruce-fir were often written from a forester's point of view, many of them 
address the lower elevational boundary, not of spruce and fir but of "spruce 
lands" (meaning forest valued for its large spruce trees which often grew, on 
good sites especially, along with hardwoods in varying unrecorded proportions). 
Furthermore, some early literature on elevational boundaries of spruce actually 
addressed the lower limit of observed individual spruce trees rather than the 
limit of spruce forest or "spruce lands." 

These differences in latitude and attitude of early writers led to a wide 
variation in conceptualized boundaries of the spruce-fir vegetation type. 
Such differences in boundaries led to difference in area estimates of extant 
spruce-fir vegetation. 

When one attempts to estimate the area spruce-fir occupied before 
disturbance of white people, a further source of variation is introduced. 
Because spruce-fir does not regenerate well (if at all) in burned cut-over 
areas and because logging followed by fire was the typical pattern of disturbance 
(Korstian 1937, Minckler 1940) in the Southern Appalachians, there are vast 
areas which may or may not have had spruce-fir vegetation prior to logging. 
Locations, as well as elevational boundaries of these areas, are open to 
debate. Hopkins (1899) was of the opinion that a large area of West Virginia, 
not then forested in spruce, once supported spruce forests in the elevational 
belt from 2400 to 4000 feet elevation. Hopkins came to this conclusion based 
on his observations of trees in stands of a few acres at elevations between 
2400 and 4000 feet coupled with his belief that, prior to settlement by the 
white people, the area was covered by an unbroken forest in which: 

"the more abundant moisture in the soil and atmosphere attending this 
forest covered condition made it possible for spruce to occupy, as the 
principal growth all of these higher elevations which at present are 
covered with other kinds of timber. The area of the belt in which 
spruce was then found, probably covered all of the higher elevations 
of the Appalachian range that rise above 2400 feet, which would be an 
area of about 2,000,000 acres, on which one-half the timber was 
probably spruce. ff so, there were about 1,500,000 acres of spruce 
forest here (in West Virginia, present author's note) when the first 
white settler occupied the territory." 



124 



Minckler (1940) apparently intuitively mistrusted Hopkins' total spruce 
acreage as he made reference to Hopkins (1899) for the estimate of 1,500,000 

acres of spruce forest prior to logging in West Virginia, Virginia, Tennessee, 

and North Carolina (whereas Hopkins' topic and discussion was on West Virginia 

a lone' . 

Clark (1954), in discussing the original spruce forests of West Virginia, 
used the number "500,000 acres." This corresponds to Hopkins (1899) if one 
leaves out Hopkins' 2,000,000 acres "on which one-half the timber was probably 
spruce." Ostensibly, this would set Clark's lower spruce forest boundary at 4000 
feet. This is higher than Froth i ngham' s (1931) estimate for West Virginia but 
not unreasonable, especially allowing for variation in definition of what 
constitutes spruce forest. 

Saunders (1979) took spruce and spruce-fir forests as those above the spruce- 
fir hardwood ecotone. Without documentation of his source of information, he 
cited 1670 meters as the "generally recognized" lower limit of spruce-fir forest 
(Saunders 1979). He then settled upon "approximately 1670 meters" (Saunders 
1979) as the elevation of the spruce-fir/hardwood ecotone. This elevation K5480 
feet), which Saunders (1979) equated to 5500 feet, is close to the 5600 feet 
! ^1 707 meters ) Whittaker (1956) used as the lower boundary of spruce and fir 
forests based on field transects on the Tennessee side of GRSM. Whittaker went 
on to describe a spruce forest (which could be up to 30 percent hardwoods or up 
to 84 percent rhododendron) at elevations from 4500 to 5500 feet (^ 1372 to 1676 
meters) in GRSM. Similarly, Schofield (I960) intimated that the hardwood/spruce 
ecotone is a gradual transition occurring from 4500 to 5000 feet (^1372 to 1524 
meters) elevation in GRSM. In taking the lower boundary of spruce-fir as 1670 
meters ( " = 5500 feet"), it appears that Saunders was thinking in terms of what 
would have been the average Southern Appalachian boundary of more or less pure 
spruce and fir rather than an intermediate point (i.e., ecotone) between spruce- 
fir and hardwoods. In fact, 5500 feet (^1676 meters) was cited by Davis (1930) 
as the lower elevation of spruce and fir forests above the spruce fir/hardwood 
ecotone on Black Mountain, North Carolina. Thus Saunders' (1979) use of 1670 
meters to define the lower boundary of spruce-fir corresponds to a narrow 
definition of what may be included in "spruce-fir" which led to a conservative 
estimate of pre- and postlogging spruce-fir area. 

Miller (1938) agreed with Schofield (I960) and Whittaker (1956) in recognizing 
nonspruce or nonfir members of the spruce forest (e.g., spruce-hardwoods, spruce- 
rhododendron). The use of Miller's map in order to estimate spruce-fir forest 
area results in numbers based on local field observations rather than on theory 
meant to cover a widespread geographic area. Miller's boundaries were based on 
field plots and ocular field mapping of vegetation extant in 1935-1938. Taking a 
closeup view through Miller's map of the Great Smoky Mountains, several patterns 
emerge: (I) truncated boundaries in burned areas, (2) the unusual Raven Fork 
watershed with its high average elevation and abundance of spruce-covered slopes, 
and (3) the general topographically influenced position of spruce forests. For 
example, the mean draw position elevation of spruce in the Bradley Fork watershed 
was 5350 feet in contrast to 4500 feet on ridges. The detailed pattern of spruce- 
fir distribution shown on Miller's map precludes taking a single map contour as 
the lower elevational boundary of past or present spruce-fir vegetation. 

Given the preceding discussion, the variability in spruce-fir areal estimates 
shown in Table 3 should not be unexpected. 

As can be seen in Table 3, there is great disagreement as to both the 
prelogging and postlogging extent of spruce-fir vegetation in the Southern 
Appalachians. However, most pre-balsam woolly aphid authors (Clark 1954, 

125 



Table 3. Areal estimates of spruce-fir vegetation 



Source 



Locat i on 



Vegetation Type - - Pre I ogg i ng"-- Post logging' 



Frot h i ngharn I 93 
Saunders 1979 
Pyle 1984 
Cruikshank 1941 



Saunders 1979 



Kor s t i an 



GRSM 


Spruce 




GRSM 


Spruce-f i r 


6,013 


GRSAA 


Spruce-f i r 


17,910 


Southern 


Spruce 


60,704 


Appa 1 ach i ans 






apparent 1 ,y 






cxc 1 us i ve of 






GRSM 






Southern 


Spruce , 


8,264 


Appa 1 ach i ans 


spruce-f i r 




exc 1 us i ve of 






GRSM 






Sou t hern 


Spruce 


404,694 


Appa 1 ach i ans 






p 1 us West 






Virginia 







18,21 I 
3,665 
! 3,370--"-: 

9,308 



3,216 



40,469 



-"-Terminology according to individual source. 

---"-AM area estimates were converted to hectares. 

-"-"-"-Based on "spruce" type shown on Frank Miller's (1935-1938) vegetative type map 



126 



Cruikshank 1941, Holmes 1911, Minckler 1940, and Schofield I960) are in agreement 
with Korstian (1937) that "the depletion of the Southern Appalachian spruce 
forest is due chiefly to fire following destructive logging." The naturally moist 
conditions of spruce-fir forests resulted in a low incidence of natural fire. 
Logging removed trees that previously had helped create the cool damp microclimate 
of this forest type. Dry conditions following logging were further promoted by 
exposure of the thick layer of soil surface organic matter to sunlight (Korstian 
1937). Unnaturally dry conditions coupled with high fuel loading from natural 
organic matter on the ground (plus addition of logging slash) made logged-over 
spruce-fir exceedingly susceptible to fire (Holmes 1911, Korstian 1937, Minckler 
1940). Ignition was readily accomplished by sparks from coal-burning logging 
equipment, escaped campfires, or lightning. Fire following logging was so common 
that, according to Korstian (1937), "Practically all cut-over spruce lands have 
been burned one or more times." 

One reason spruce-fir logging was destructive, especially in the early 1900s, 
was that most areas were then being logged for pulp by mechanized equipment. Trees 
of smaller diameter than sawtimber were acceptable for pulp, so more trees were 
removed and more low quality sites were logged. The mechanized logging equipment 
destroyed both the soil and advance reproduction. Such logging practices made the 
area prone to erosion as well as fire (Korstian 1937). 

Not all logging in spruce-fir forests resulted in creation of sites unsuitable 
for spruce or fir regeneration. In fact, regeneration could be very good where 
fire was excluded (Holmes 1911, Minckler 1940). However, where spruce was removed 
from mixed hardwood/spruce forests, reproduction of spruce was not good due to 
thick hardwood litter (Korstian 1937, Schofield I960). 

Overall, the I ogg i ng- i nduced loss of spruce-fir in the Southern Appalachians 
was due both to destruction of soil organic matter by logging slash fires (and, to 
some extent, erosion) and encroachment of logged sites by hardwoods. 

In GRSM, spruce-fir logging operations were frequently followed by fire. 
Reasons for prevalence of fire have been discussed above. Fire may have been 
avoided in areas where high-grading took place. For example, in the East Prong of 
the Little River, areas such as Goshen Ridge were high-graded for spruce. Also, 
in the Cataloochee watershed, the area north and south of Poll's Gap was high- 
graded for valuable trees, including spruce. Though logged prior to the drought 
year of 1925, neither of these areas burned immediately following logging nor 
during 1925 when nearby areas burned. 

The method used fc this paper in determining extent of spruce-fir prior to 
logging did not address loss of spruce due to lack of regeneration in unburned 
spruce-hardwood or spruce-hemlock stands. This loss was probably not significant 
in the East Prong of the Little River nor in the upper reaches of Noland Creek, 
where a truncated spruce vegetation boundary on a minor ridges suggests removal of 
some outlying spruce. Loss of spruce may have been important in Straight Fork and 
possibly Bunches Creek and Cataloochee as well. 

The ridge area (typed as northern hardwoods by Miller) near Poll's Gap between 
Cataloochee and Bunches Creeks is relatively low in elevation and somewhat far 
removed from the main crest of the Great Smoky Mountains. Whittaker (1956), in 
discussing the southwestern boundary of spruce distribution in GRSM, postulated 
that the climatic warming period some 4000 years ago drove the lower spruce 
boundary up to elevations of 5700 feet. This resulted in spruce having to reinvade 
lower areas from peaks of over 5700 feet. South of Poll's Gap there are no such 
peaks in GRSM. However, spruce stumps seen by the author indicate spruce was 
definitely present south of Poll's Gap. To determine if spruce was once important 
enough to have made the forest a spruce type by SAF standards would require field 
work that was beyond the scope of this report. 

127 



In the Straight Fork watershed there is record of "a good deal of spruce" 
taken from Dan's Branch in 1 9 1 8- 1 9 1 9 (Lambert 1958). This area was shown as 
spruce on Miller's map. There is also record of logging (species not documented) 
in Balsam Corner Creek. Very little of this area was typed as spruce by Miller. 
I concluded that if a good deal of spruce removed from Dan's Branch did not 
change the vegetation type, it would not have done so in the adjacent unburned 
Balsam Corner Creek. 

There is a weakness to this rationale in that Straight Fork is topographically 
different from the adjacent major watersheds which are covered or believed to 
have been previously forested in spruce. Both Dan's Branch and Balsam Corner 
Creek are quite concave in comparison to the adjacent headwaters of Cataloochee 
Creek. They are also lower in average elevation than Raven Fork watershed to the 
west. Further, Balsam Corner Creek is not nestled up to the mountain mass of the 
Smoky Mountains which supported we I I -deve I oped spruce and fir. These topographic 
characteristics combined in Balsam Creek may have resulted in the presence of 
spruce, not as a dominant species but rather as large individuals in mixed stands 
with hardwoods or hemlock. If large amounts of spruce were selectively removed 
from such mixed hardwood or hemlock stands in Balsam Corner Branch, then the 
present pattern of hardwood and hemlock cover would indicate a loss of spruce. By 
this interpretation, Dan's Branch supports we I I -deve I oped spruce because it is 
geographically closer to the main mountain mass than Balsam Corner Creek. 

Because hardwood overstory encroachment resulting in conversion of cut-over 
mixed spruce-hardwood stands to hardwood types was not considered in the present 
author's estimates of spruce-fir loss in GRSM, the totals given for original 
spruce-fir area may be conservative in logged but unburned areas. Possibly 
significant logged but unburned areas in GRSAA are Straight Fork and, to some 
extent, the Caldwell Fork portion of Cataloochee and the higher elevations of the 
southeastern corner of Bunches Creek. 

In the Cataloochee watershed, E. J. Rosser (a logging engineer hired to 
cruise timber for the North Carolina Park Commission (NCPO)gave a total of 1662 
acres (^673 hectares) of "spruce soil" (Box I I I -6 , Suncrest Lumber Company 
Papers, GRSM Archives). This total included 422 acres ( % 171 hectares) of 
cut-over spruce in the Caldwell Fork drainage (i.e., in the area of aforementioned 
spruce and hardwood forest north and south of Poll's Gap). Four hundred 
twenty-two acres of spruce was a generous estimate for this area, considering its 
low elevation and the fact that the unlogged area to the south supports no spruce 
at all. 

The 124-0 acres ( %502 hectares) remaining of Rosser ' s 1662 acres were located 
in the upper elevations of Big Cataloochee Creek. Based on Miller's map (which 
had no spruce in Cal dwe II Fork), the author estimated there were 404 hectares 
( %998) acres ) of spruce fir extant in Cataloochee. It seems likely that Rosser 
included these 998 acres in his 1240, plus another 242 acres (^98 hectares) in 
burned or unburned areas that he had reason to believe could still support spruce. 

A line of reasoning such as outlined above would have been likely for someone 
attempting to place a value on the land NCPC was acquiring. It does not help one 
working 50 years later in determination of the original extent of spruce-fir 
forest. The reconstruction of spruce-fir forest boundaries in Cataloochee Creek 
was based on the best historic evidence available (i.e., old maps and 
correspondence). The reconstructed boundaries represent, to a great extent, 
spruce boundaries defined by an anonymous mapmaker's unrecorded assumptions as to 
what constitutes spruce forest. 

Estimation of loss of original spruce-fir forest cover in Big and Forney Creeks 
was based on estimation of pre I ogg i ng-era spruce acreage. Again, the assumptions 
concerning what constitutes spruce forest, on which these estimates were made, 
are not known. Given that the estimates of spruce for these three watersheds 

128 



( Cata I oochee , Big, and Forney Creeks) were made by people interested in 
exploitation of spruce, it is likely their estimates of spruce lands reflected 
the fact that, in some areas, spruce was the only tree worth cutting, even it it 
was not the dominant forest canopy cover. Consequently, the numbers derived from 
these estimates and given in Table I under "cut and burned" spruce-fir type may be 
overest imat ions for Cataloochee, Big, and Forney Creeks. 

CONCLUSION 

The halting of loggers in GRSM by the move to acquire timber company lands for 
the impending national park left extant 75 percent (13,370 hectares) of the 
estimated original 17,910 hectares of spruce-fir forest. This continuous spruce- 
fir cover, extending 56 kilometers along the crest of the Great Smoky Mountians, 
is the largest remaining block of the 404,694 hectares of spruce forest estimated 
by Korstian (1937) to have once covered the mountains of West Virginia, Virginia, 
Tennessee, and North Carolina. Most (12,100 hectares) of the spruce-fir left in 
GRSM was untouched by loggers and presents the ideal opportunity in which to study 
spruce-fir. Prior to recent disturbance of Fraser fir by the balsam woolly aphid, 
the Middle Prong watershed (in Tennessee) plus the adjacent Raven Fork and (in part) 
Straight Fork watersheds (in North Carolina) contained a large unbroken expanse of 
we I I -deve I oped spruce-fir forest extending the full elevational range of the type 
in GRSM from below 4000 feet (^1220 meters) to over 6500 feet (%I980 meters). Even 
following balsam woolly aphid infestation, Raven Fork, with its high percentage of 
unlogged spruce-fir forest, remains overall the least disturbed watershed in GRSM. 



129 



REFERENCES CITED 

Ayres, H. B., and W. W. Ashe. 1902. Forests and forest conditions in the 

Southern Appalachians. In Theodore Roosevelt, Message from the President of 
the United States: Transmitting a report of the Secretary of Agriculture in 
relation to the forests, rivers, and mountains of the Southern Appalachian 
region. Senate Document No. 84. Washington, DC, p. 45-59. 

Ayres, H. B., and W. W. Ashe. 1905. The Southern Appalachian forests. U.S. 
. Geological Survey Professional Paper No. 37, Washington, DC. 291 p. 

Buckley, S. B. 1859. Mountains of North Carolina and Tennessee. Am. J. Sc i . and 
Arts (Second Series) 27:286-294. 

Davis, J. H., Jr. 1930. Vegetation of the Black Mountains of North Carolina: an 
ecological study. J. Elisha Mitchell Sc i . Soc . 45:291-318. 

Holmes, J. S. 1911. Forest conditions in western North Carolina. North Carolina 
Geologic and Economic Survey Bull. 23:1-116. 

Hopkins, A. D. 1899. Report on investigations to determine the cause of unhealthy 
conditions of the spruce and pine from 1880-1893. West Virginia Agric. Exp. 
Stn. Bull . No. 56, p. 194-461 . 

Korstian, C. F. 1937. Perpetuation of spruce on cut-over and burned lands in the 
higher Southern Appalachian Mountains. Ecol. Monogr . 7:125-167. 

Lambert, R. S. 1958. Logging in the Great Smoky Mountains National Park. Unpubl. 
Rep. to the Superintendent. 71 p. 

Minckler, L. S. 1940. Early planting experiments in the spruce-fir type of the 
Southern Appalachians. J. For. 38:651-654. 

Panshin, A. J., E. S. Harrar, J. S. Bethel, and W. J. Baker. 1962. Forest 

products, their sources, production, and utilization, 2nd ed. McGraw-Hill Book 
Co. , I nc . , New York . 

Saunders, P. R. 1979. The vegetational impact of human disturbance on the spruce 
fir forests of the Southern Appalachians. Ph.D. Dissert., Duke Univ., Durham, 
NC. 177 p. 

Schofield, W. B. I960. The ecotone between spruce-fir and deciduous forest in the 
Great Smoky Mountains. Ph.D. Dissert., Duke Univ., Durham, NC . 176 p. 

Society of American Foresters. 1954. Forest cover types of North America 
(exclusive of Mexico). Rep. Comm. on For. Types. 67 p. 

Whittaker, R. H. 1956. Vegetation of the Great Smoky Mountains. Ecol. Monogr. 
26: 1-80. 



130 



A STATUS REPORT ON BRYOPHYTES OE THE SOUTHERN 
APPALACHIAN SPRUCE-FIR FORESTS 



David K. Smith 1 

Abstract. Bryophytes of the spruce-fir forests of the southern 
Appalachians are discussed in terms of historical, floristic, 
phytogeographic, and ecological knowledge. Rare and critical species 
commonly associated on fir will reguire careful monitoring to formulate 
management strategies for their preservation given the rapid decline 
of Fraser fir from balsam wolly aphid destruction of the forests. 

Any discussion of the bryoflora of the spruce fir forests of the southern 
Appalachians is handicapped by the lack of information for many of the stands of 
spruce and fir isolated along the mountain crests of the region. The most complete 
knowledge available is that of the Great Smoky Mountains. While this discussion 
draws heavily upon the investigations of bryophytes in the spruce-fir of the Smokies, 
it is reasonable to assume that other areas will show a high degree of similarity 
when they become investigated. 

The area described within the boundaries of the Great Smoky Mountains National 
Park represents a significant subset of the natural biological resources of the greater 
southern Appalachian region. This region has long been acclaimed for its high 
diversity of species reflecting a long, rather stable history, that has been periodically 
enriched by floral and faunal elements from adjacent regions. Sharp (1941) and 
others have attempted to account for the peculiar mixture of floristic elements in 
the Smokies by drawing attention to the influences of "prehistoric phenomena" (e.g. 
glaciation, oceanic transgression, and orogenic activity) that have variously affected 
earth history in eastern North America. 

Focus has come to bear on the high elevation forests of the southern 
Appalachians because of accelerating destruction of Fraser fir by the balsam wooly 
aphid and general threats to this forest ecosystem resulting from concentrated loads 
of atmospheric pollutants. Spruce and fir forests are the dominant structural unit 
of the high montane portions of the southern Appalachians. The significance of 
this irreplaceable forest ecosystem is succinctly described by Sharp (1941) as " . . . 
the largest stands of relatively homogeneous nature are those of the Fraser fir on 
the high tops and of red spruce just below. These are the largest virgin areas of 
these species in the eastern United States." 



David K. Smith, Department of Botany, The University of Tennessee, Knoxville, 
Tennessee, 37916, U.S.A. 



131 



BRYOPHYTES OF THE SOUTHERN APPALACHIAN SPRUCE-FIR FORESTS 



Floristic and Phytogeographic Discussions 

A total of 1690 species of bryophytes (plus nearly 400 subspecific taxa) are 
currently ascribed to North America (including the conterminous United States, 
Canada, Alaska, and the Aleutian Islands). Mosses comprise the majority with I 170 
species (Crum, Steere, Anderson 1973) and the remaining 526 species are liverworts 
(Stotler and Stotler, 1977). 

Sharp (1939) listed 426 species of bryophytes in eastern Tennessee alone, roughly 
equivalent to 25% of the total North American complement. Of these, more than 
325 species including over 100 liverworts inhabit the Smokies (Sharp, 1941). Ecological 
investigations of bryophyte communities in the spruce-fir zone by Cain & Sharp 
(1938) treated 81 species, at that time, thought to represent approximately one- 
third of the total spruce-fir bryoflora. A more detailed study of the spruce-fir of 
the Smokies by Norris (1964) documented 203 species as present. A reasonable total 
estimate of the bryophytes of the spruce-fir might increase the number by no more 
than 15% to approximately 235 species. 

The rich diversity of bryophytes in the spruce-fir is a distinctive feature of 
the forest. Furthermore, in abundance, they form a conspicuous part of the terrestrial 
and epiphytic flora. Species richness and abundance is a result of the cool moist 
climate and floristic enrichment by northern, southern and rare disjunctive elements. 

Elements of boreal, coastal plain, and subtropical bryofloras have merged and 
persisted in numerous, narrowly defined habitats within the spruce-fir forest. By 
far the majority of species are allied to the north temperate or subarctic-alpine 
zones, especially the circumboreal belt of the northern coniferous forest. 

Common and abundant species such as Dicranum spp., Polytrichum spp., 
Sphagnum spp., Hylocomium splendens (Hedw.) B.S.G., and Rhytidiadelphus triquetrus 
(Hedw.) Warnst. form extensive clumps and mats as is typical in the circumboreal 
forest. Less conspicuous and less abundant members of the northern forest and 
subarctic alliances of bryophytes include mosses such as Arctoa fulvella (Dicks.) B.S.G. 
[= Dicranum fulvellum, Sharp 1936b, unverified by Crum and Anderson 1981], Blindia 
acuta (HedwT) B.S.G., Dichodontium pellucidum (Hedw.) Schimp. [= Oreoweisia 
serrulata , Sharp 1939b], Hygrohypnum spp., Hylocomium umbratum (Hedw.) B.S.G., 
Oncophorus wahlenbergii Brid., Paraleucobryum longifolium (Hedw.) Loeske, Pohlia 
cruda (Hedw.) Lindb., P~ohlia elongata Hedw., Racomitrium aciculare (Hedw.) Brid., 
Racomitrium heterostichum (Hedw.) Brid., and Rhytidiadelphus squarrosus (Hedw.) 
Warnst. Liverworts such as Anastrophyllum minutum (Sc.hreb.) Schust., Anastrophyllum 
michauxii (Web.) Buch ex Evans [= Sphenolobus michauxii , Norris 1964], Bazzania 
spp., Blepharostoma trichophyllum (L.) Dum., Cephalozia spp., Gymnocolea inf lata 
(Huds.) Dum., Jungermannia atrovirens Dum. [= Jungermannia lanceolata , Norris 
I 964], Lophozia spp., Marsupella emarginata (Ehrh.) Dum., Tritomaria ssp., and others 
are additional evidence of a northern influence. 

Less extensive, although more critical, components of the spruce-fir bryoflora 
are associated with specific substrates. While many species form neat, predicatable 



132 



associations, others are quite sporadic in their occurrences. In particular, rock 
outcrops and live Fraser fir are the most critical habitats. 

Some of the more "precious" species exhibit wide-ranging, disjunctive world 
distributions. Others are rather narrow endemics of eastern montane North America 
or strictly of the southern Appalachians. Whereas, only a few species of eastern or 
all of North America, are restricted to the spruce-fir zone, a more substantial list 
of endemics and/or disjuncts can be constructed by including species predominantly 
of mid- and low elevations that also occur in the spruce-fir. 

Only a few mosses fit patterns of major disjunction or endemism, although 
the number of examples of such among liverworts is more impressive. This, in part, 
reflects differences in the modern taxonomy of both groups as well as an especially 
rich biotypic liverwort flora within the southern Appalachian mountain system 
(including the eastern escarpment of the Blue Ridge gorge system). 

Leptodontium excelsum (Sull.) Britt. and Pterigynandrum sharpii Crum et 
Anders. [ = Hylocomium splendens var. tenue, Sharp 1 933 ] are the only two mosses 
that fit a strict pattern of spruce-fir endemism. Leptodontium is nearly restricted 
to the bark and twigs of Abies and Pterigynandrum appears exclusively on very 
moist, shaded rocks between 4000 and 5500 ft. elevations. Both species are regarded 
as rare within their total ranges. 

Fissidens appalachensis Zand., Oncophorus rauii (Aust.) Grout, and 
Brachydontium trichodes (Web.) Milde are outstanding examples of unusual endemic 
and disjunct mosses in the spruce-fir forests. Fissidens, a southern Appalachian 
endemic, is an aquatic species originally described from and regarded as a mid- 
elevation Blue Ridge gorge species. It has been reported once from Roan Mountain, 
Tennessee above 5000 ft. elevation. Oncophorus is an Appalachian endemic, occurring 
in Pennsylvania and skipping south to the mid- and upper elevations of Georgia, 
North Carolina, South Carolina, and Tennessee. Brachydontium exhibits a sporadic 
and disjunctive distribution (the peaks of North Carolina and Tennessee, New 
Hampshire, Washington, northern and central Europe, British Isles, and Caucauses) 
that may be explained as a Tertiary relict. 

A more peculiar pattern of distribution is shown by Isothecium stoloniferum 
Brid. ( sensu Crum & Anderson 1981, reported as Pseudisothecium myosuroides Gott., 
Sharp I 936b). This moss is common and widely distributed in western North America, 
becoming less frequent in the eastern portion of its range, there occurring in eastern 
Canada, upper New England, and jumping south to the spruce-fir of Tennessee and 
North Carolina. Closely related if not identical, Isothecium myosuroides Brid. occurs 
in similar habitats of northern, central, and western Europe (Crum & Anderson, 1981). 

A number of liverworts exhibit somewhat parallel patterns of distribution 
similar to the moss endemics and disjuncts. 

Bazzania nudicaulis Evans is the only example of a strict spruce-fir endemic, 
occurring only on the highest peaks mostly above 5500 ft. elevation in the southern 
Appalachians. 

Several other southern Appalachian endemics are more generally distributed 
among hardwood forests of the mid- and lower elevations, but range upwards in 



133 



elevation to the lower fringes or well into the spruce-fir zone. As examples of 
this distributional pattern one may cite Drepanolejeunea appalachiana Schust., 
Lejeunea ruthii (Evans) Schust., Plagiochila caduciloba Blomq., P. sharpii Blomq., 
and P_. sullivantii Gott. ex Evans. 

Three additional species exhibit even wider patterns of endemism. Lejeunea 
lamacerina subsp. gemminata Schust. and Plagiochila austinii Evans are confined to 
the Applachian region, extending from Nova Scotia in the north (infrequent) south 
through New England, the central Appalachians and into Georgia, North Carolina, 
and Tennessee. Leucolejeunea clypeata (Schwein.) Evans fits into a pattern of 
eastern North American distribution. Schuster (1980) considered this species as 
Appalachian with a post-Pleistocene radiation west to Oklahoma, east throughout 
the Piedmont and Coastal Plain, and south into Florida. 

Several species of North American or wider patterns of disjunct distribution 
further enrich the spruce-fir bryoflora. Marsupella funckii (Web. et Mohr) Dum. 
occurs in the southern Appalachians and again in the Great Lakes Region. 
Sphenolobopsis pearsonii (Spr.) Schust. & Kitag. and Plagiochila corniculata (Dum.) 
Dum. occur at high elevations in the southern Appalachians and in western Europe; 
the former species also occurring in the Pacific Northwest and Japan. Acrobolbus 
ciliatus (Mitt.) Schiffn. [= Acrobolbus rhizophyllus Sharp 1936a] is considered an 
ancient species of Tertiary age, widely disjunct and occurring in Himalaya, Japan, 
Aleutian Islands, and the southern Appalachians. 

Rock outcrops, although a fractional component of available substrate in the 
spruce-fir zone, contain one of the most unique communities of bryophytes. Schuster 
(1974) stressed the critical importance of liverwort associations found on the highly 
exposed crevices and surfaces of rocks at high elevations in the southern Appalachians. 
Gymnomitrion laceratum (Steph.) Horik., Marsupella funckii , Marsupella paroico 
Schust., Cephaloziella massalongi (Spruce) K. Muell., Microlepidozia sylvatica (Evans) 
Joerg., Mylia taylori (Hook.) S.F. Gray, and Nardia scalaris (Schrad.) S.F. Gray form 
an important association of species with endemic, disjunctive, widespread, 
predominantly northern and Coastal Plain distributions. 

Gymnomitrion laceratum is extremely rare with a North American distribution 
that is restricted to four localities in Tennessee (Mt. LeConte and Mt. Kephart) 
(Schuster 1974). It is an extreme disjunct, occuring elsewhere in mountainous regions 
of Japan, tropical east and south Africa, South America, and Mexico. Nearly parallel 
patterns of distribution are shared in this association by Marsupella funckii , 
Cephaloziella massalongi , and Nardia scalaris, but all three lacking in the Southern 
Hemisphere (Shuster 1974). Marsupella paroica is an eastern North American 
endemic centered in the southern Appalachians where it occurs from the mid- 
elevational deciduous (cool and moist) to the upper limits of spruce-fir forests and 
jumping to a few locations in the Great Lakes Region. Mylia taylori and Nardia 
scalaris illustrate circumboreal patterns of distribution with sporadic occurrences in 
all continents of the Northern Hemisphere. In North America they follow "oceanic 
tendencies" indicated by occurrences in the Pacific Northwest (including Alaska) and 
Atlantic Coastal upper East x and Canada. Their occurrence in the southern 
Appalachian spruce-fir is regarded by Schuster (1969) as relict. Microlepidozia 
sylvatica and Cephaloziella massalongi are more limited in their distributions. Both 
exhibit trans-Atlantic distributions, the former more abundant in eastern North 
America where it is common in the Coastal Plain and penetrating to the high ridges 



134 



of the Appalachian Plateau; the latter most common in Europe and reported in 
North America only from Vermont and Tennessee. 

Live Fraser fir must be regarded as the most critical habitat of the spruce-fir 
forest. Not only is fir the dominant canopy species (Cain 1935) above 6000 ft. 
elevation, the bole, branch and twig flora of bryophytes and lichens is extremely 
rich, distinctive, and often a restrictive substrate. 

Table I lists 36 species of mosses and liverworts that freguently occur growing 
on the bark of fir. Of these, two mosses, Leptodontium excelsum and Zygodon 
viridissiumus (Dicks.) Brid., and four liverworts Bazzania nudicaulis, Leptoscyphus 
cuneifolius (Hook.) Mitt., Plagiochila corniculata, and Sphenolobopsis pearsonii are 
nearly resticted to fir. Of these species not previously discussed, Leptoscyphus is 
considered by Schuster (1980) to be an ancient oceanic species confined in North 
America to the high elevation southern Appalachians, elsewhere with a north and 
south (antipodal) oceanic and montane tropical distribution. Zygodon is an equally 
widely disjunct species occurring in Michigan, Nova Scotia, Quebec, northern and 
central Europe, Japan, Himalaya, and Venezuela (Crum & Anderson, 1981). 

Table I. Bryophytes reported on Fraser Fir (compiled from Cain & Sharp 1 938 , 
Norris 1964, Schuster 1969, 1974, 1980). 



HEPATICAE MUSCI 

Anastropyllum michauxii Brotherella recurvans (Michx.) Fleisch. 

(Web.) Buch ex Evans Dicranum fuscescens Turn. 

Bazzania denudata Hylocomium splendens (Hedw.) B.S.G. 

(Tor. ex Gott. et. al.) Trev. Hylocomium umbratum (Hedw.) B.S.G. 

Bazzania nudicaulis Evans Hypnum pallescens (Hedw.) P.- Beauv. 

Bazzania trilobata (L.) S. Gray Leptodontium excelsum (Sull.) Britt. 

Blepharostoma trichophyllum (L.) Paraleucobryum longifolium (Hedw.) Loeske 

Dum. Plagiothecium laetum B.S.G. 

Cephalozia lunulifolia (Dum.) Dum. Polytrichum ohioense Ren. & Card. 
Frullania asagrayana Mont. Ptilium crista-castrensis (Hedw.) De Not. 

Frullania oakesiana Aust. Rhytidiadelphus triquetrus (Hedw.) Warnst. 

Geocalyx graveolens (Schrad.) Nees Tetraphis pellucida Hedw. 
Harpalejeunea ovata (Hook.) Thuidium delicatulum (Hedw.) B.S.G. 

Schiffn. Ulota crispa (Hedw.) Brid. 

Herberta tenuis Evans Zygodon viridissimus (Dicks.) Brid. 

Jamesoniella autumnal is (D.C.) Steph. 
Lejeunea ruthii (Evans) Schust. 
Lejeunea ulicina (Tayl.) Gott. 
Lepidozia reptans (L.) Dum. 
Leptoscyphus cuneifolius (Hook.) Mitt. 
Lophozia incisa (Schrad.) Dum. 
Metzgeria temperata Kuwah. 
Plagiochila corniculata (Dum.) Dum. 
Plagiochila sharpii Blomq. 
Sphenolobopsis pearsonii (Spruce) Schust. 
Tritomaria exsecta (Schrad.) Loeske 



135 



Ecology and Community Structure 

Two studies stand as major investigations of bryophytes in the spruce-fir forests. 
Cain and Sharp (1938) described bryophytic unions of the Great Smokies based upon 
quadrat and map samples. Their descriptions of spruce-fir communities were 
amplified considerably by Norris (1964) who devoted his investigation exclusively to 
the spruce-fir zone. 

The study by Cain and Sharp (1938) delineated bryophyte unions among three 
principal forest associations of the spruce-fir zone. They sampled Fraser fir forest 
on Mt. Leconte, red spruce forest on Mt. Mingus, and American beech forest on 
Trillium Gap. Fourteen unions and several subordinate facies and unstructured 
associules were distributed among the three forest types: eight unions within the 
Abietum fraseri Association, four unions within the Piceetum rubentis Association, 
and two unions within the Fagetum grandifloriae subalpinum Association. 

A total of 81 species sampled in their investigaton were distributed among 
the three forest associations. Forty-seven species occurred in the Fraser fir forest, 
27 species (only two not found under fir) in spruce forest, and 28 species (22 
exclusive to beech forest) in beech forest. These figures suggest that nearly half 
of the bryophytes occurring in fir forest might be severely impacted by altering 
the canopy structure. The high number of species exclusive to beech forests reflects 
the northern and cove hardwoods bryofloristic influence. 

The significance of fir as an important substrate is attested to by the fact 
that five of the eight unions of this association occurred on either live, standing 
dead, or fallen trees. Standing dead or fallen fir had the highest diversity of species 
(26) distributed among four unions; but these values reflect compositional changes 
during stages of decay and ecesis. Living fir supported two unions and one facie 
along with 22 associated species. 

Norris' study (1964) is more detailed than that of Cain and Sharp. His study 
increased the species list to 203 species and delineated 22 unions for the spruce- 
fir forest. While this study attempted to classify bryophytes objectively on the 
basis of species associations, one must refer to descriptions of each union to 
determine substrate identities. Unstated by Norris is the fact that 31 species were 
restricted to one or two unions or substrates; giving notice to the rather narrow 
ecological limits for those species. 

Impacts From Fraser Fir Deforestation 

The depletion of Fraser fir in the southern Appalachians poses a major threat 
to the rich diversity and abundance of bryophytes of high elevation forests. Species 
diversity and abundance is a direct reflection of microclimatic and substrate diversity. 
Live, standing dead, and fallen fir are important substrates that cycle through a 
healthy enduring forest. A continuum of combinations of both moisture and 
illumination is created as natural death and replacement occurs in fir forest. Small 
windows form in the canopy as trees die and defoliate. The dimensions of openings 
increase when trees fall, allowing greater penetration of light and further shifts in 
moisture at the forest floor and along the edges of openings. Decortication and 
humification of fir logs represent the final stages of substrate cycling. 



136 



Death of large tracts of mature fir will undoubtedly shift the equilibrium of 
abiotic factors in the primeval forest. Illumination values will increase and superficial 
drying of the forest floor will ensue. Initially, standing dead trees will dominate. 
Finally, as limbs prune and boles fall, the forest floor will be smothered by the 
skeletons of the original forest. Processes of decay and bryophyte succession on 
logs will dominate if conditions of moisture and light are not too extreme. The 
canopy will be replaced by a more heterogeneous mixture of northern hardwoods 
and spruce, ultimately favoring bryophytes of those forest types. 

It is this writer's opinion that rapid and large scale death of mature fir forest 
will severely impact the distinctive bryoflora of fir. The abundance of rare species 
will decline and some extirpations are probable. 

Research priorities 

The investigations of Cain and Sharp (1938) and Norris ( 1 964) have provided 
an excellent working knowledge of the bryoflora and its community structure within 
the spruce-fir that predate the infestations by the balsam wolly aphid. There still 
remains room for more detailed studies of bryophytes in pure fir stands to more 
carefully assess total diversity, abundance, and ecosystem role. 

Epiphytic, terrestrial, and epilithic habitats of fir forest should be restudied 
in intact forest and compared to parallel studies of lightly and heavily disturbed 
forest. A most important consideration should be the determination of rates and 
degrees of bryophyte depletion on live fir. Secondary considerations should be given 
to evaluating alternate hosting of rare epiphytic species and changes in the abundance 
of terricolous and epilithic species. 

Virtually nothing is known concerning nutrient partitioning, cycling, water 
relations, or the bryhophyte microcosm in the spruce-fir. It has been speculated 
that epiphytic species act as wicks or nets to entrap moisture in fog belts. This 
undoubtedly benefits the bryophytes by maintaining compensation levels of hydration, 
but may also act as a drip system for irrigating the forest floor. Thick mats of 
mosses on the forest floor may function as sponges to retard moisture and nutrient 
loss. Bryophyte-microfaunal-microfloral associations are well known to bryophyte 
taxonomists. Only a few studies have actually been conducted to investigate these 
microscopic communities, none of which treat habitats in spruce-fir. 

Although the effects of atmospheric pollution on the vigor of bryophytes has 
not been documented for the spruce-fir forest, this subject should be examined along 
with well-documented effects known to adversely affect lichens. It has been clearly 
demonstrated that terrestrial bryophytes concentrate heavy metal pollutants and 
such a role for spruce-fir bryophytes should be examined. 



137 



LITERATURE CITED 



Cain, S.A. 1935. Ecological studies of the vegetation of the Great Smoky Mountains. 
II. The quadrat method applied to sampling spruce and fir forest types. Am. 
Midi. Nat. 16: 566-584. 

, and A.J. Sharp. 1938. Bryophytic unions of certain forest types of the 



Great Smoky Mountains. Am. Midi. Nat. 20: 249-301. 

Crum, H.A. and L.E. Anderson. 1981. Mosses of Eastern North America, Vol. I & II. 
Columbia University Press, New York. 

, W.C. Steere and L.E. Anderson. 1973. A new list of mosses of North 



America North of Mexico. Bryologist 76: 85-130. 

Norris, D.H. 1964. Bryoecology of the Appalachian Spruce-Fir Zone. Ph.D. 
Dissertation, University of Tennessee, Knoxville, Tennessee. 

Schuster, R.M. 1969. The Hepaticae and Anthocerotae of North America, Vol. II. 
Columbia University Press, New York. 

. 1974. The Hepaticae and Anthocerotae of North. America., Vol. III. 



Columbia. University Press, N.Y. 
. 1980. The Hepaticae and Anthocerotae of North America, Vol. IV. 



Columbia University Press, New York. 
Sharp, A.J. 1933. Three new mosses from Tennessee. Bryologist 36: 20-23. 

. 1936a. Acrobolbus in the United States. Bryologist 39: 1-2. 

1936b. Interesting bryophytes, mainly of the southern Appalachians. 



J. South. Appal. Bot. Club. I: 49-59. 

, . 1939. Taxonomic and ecological studies of eastern Tennessee 



bryophytes. Am. Midi. Nat. 21: 267-354. 

1941. Some historical factors and the distribution of southern 



Appalachian bryophytes. Bryologist 44: 16-18. 

Stotler, R. and Barbara Crandall-Stotler. 1977. A checklist of liverworts and 
hornworts of North America. Bryologist 80: 405-428. 



138 



LICHENS OF THE SOUTHERN APPALACHIAN MOUNTAIN SPRUCE-FIR ZONE 
AND SOME UNANSWERED ECOLOGICAL QUESTIONS 

Jonathan P. Dey 

Abstract . — Species composition, general substrate affinities, 
floristic relationships, and uniqueness of the macrolichen flora 
of the high-mountain areas of the southern Appalachian Mountains 
are known. Attention needs to be given to the microlichen flora 
of the region and to obtaining quantitative data on the structure 
of lichen communities and their importance in local ecosystems. 
The consequences of the balsam woolly aphids' continuing 
destruction of Fraser fir trees on the composition and structure 
of lichen communities in the spruce-fir forest need to be 
ascertained. Lichens should be utilized as biomonitors of air 
pollution in the spruce-fir zone. 

Additional keywords: Abies fraseri , Adelges piceae , lichens as 
biomonitors, air pollution and lichens, island biogeography 

At various sites within the southern Appalachian spruce-fir zone, 
lichenized ascomycete fungi form a very conspicuous part of the local 
vegetation as epiphytes on coniferous and deciduous trees, as ground cover 
organisms, or as rock cover organisms. Any consideration of the status of 
lichens or the current role of lichens in the southern Appalachian spruce-fir 
ecosystem must include an analysis of what is known about the lichens locally 
and what still needs to be determined about them. With the conspicuous, 
ongoing destruction of Fraser fir [ Abies fraseri (Pursh) Poir.] by the balsam 
woolly aphid ( Adelges piceae Ratz.) and the subtle effects of air pollution 
both threatening to irreversibly alter the southern Appalachian spruce-fir 
ecosystem, it is timely to evaluate the lichens and their role in the 
ecosystem. 

LICHENS OF THE SOUTHERN APPALACHIAN SPRUCE-FIR ZONE 

Our knowledge of the fruticose and foliose macrolichen flora of the 
southern Appalachian spruce-fir zone is excellent. The studies by Degelius 
(1941), Moore (1963), Perry and Moore (1969), and Dey (1978) are the most 
comprehensive ones of the region. In the only study specifically of the 
lichen flora of the high-mountain areas of the southern Appalachians above 
1676 m (5500 ft.), Dey reported 178 macrolichen species. Subsequent 
refinement of taxonomic concepts brings the total to at least 181 
macrolichens in the high-mountain areas with the addition of Cetrelia 
monochorum (Zahlbr.) Culb. & Culb., Hypogymnia appalachensis Pike, and 
Hypotrachyna showman ii Hale to the list. Most remaining taxonomic problems 
are restricted to the genus Usnea . 

In contrast, our knowledge of the crustose microlichen flora of the 
spruce-fir zone is very uneven. The preliminary annotated list of crustose 



Associate Professor of Biology, Department of Biology, Illinois Wesleyan 
University, Bloomington, Illinois, 61701, U.S.A. 

139 



species in the Great Smoky Mountains National Park prepared by Degelius 
(19^1) is particularly valuable. Many lichenologists have made general 
collecting trips in the southern Appalachians including the spruce-fir zone 
and have identified crustose specimens. However, their collections have been 
used primarily as regional reference specimens in herbaria or as research 
specimens for monographic studies rather than as the basis of a comprehensive 
investigation of the southern Appalachian crustose lichen flora. 

Species-substrate and species-plant community relationships 

Although collections of southern Appalachian macrolichens have never 
been made using a statistically valid sampling method to provide sound 
quantitative data of the lichen vegetation, examination of label data of 
macrolichen specimens housed in the Duke University herbarium provide 
considerable information about species-substrate relationships and 
species-vascular plant community relationships of the macrolichens in the 
southern Appalachian spruce-fir zone. The following observations will 
supplement and complement those made previously by Dey (1978). 

In a consideration of the spruce-fir ecosystem, epiphytic macrolichens 
which occur on Fraser fir, red spruce ( Picea rubens Sarg.), mountain ash 
( Sorbus americana Marsh.), and yellow birch ( Betula lutea Michx.) are 
probably of greatest interest and importance. Fraser fir and red spruce, the 
only conifer trees, dominate the forest and its canopy while mountain ash and 
yellow birch, the most important deciduous trees, are only of minor 
significance in the forest canopy. Of these four trees in the spruce-fir 
forest, only the yellow birch is ah important tree species in the deciduous 
forest beneath the spruce-fir forest and the various fire cherry communities 
(see Ramseur, 1960) successional to the spruce-fir forest. Consequently, 
examination of occurrence records of macrolichens on these four tree species 
will provide useful information about the corticolous macrolichen flora of 
the spruce-fir forest. That the diversity and frequency of lichens on Fraser 
fir are much greater than on red spruce is illustrated in Table 1. Evidently 
physical characteristics, such as flakiness, and chemical characteristics of 

Table 1 . Numbers of macrolichen species epiphytic on Fraser fir , red spruce , 



mountain ash, 
high-mountain 


and yellow 
areas 


birch trees 


in the 


sou 


thern Appalachian 


Substrate 




Number of 


lichen species collected 




tree 
species 


Total 


Twice of 
more 




Once 
only 


Not on 
fir 




Not on fir & 
other 2 trees 


Fraser fir 
Red spruce 
Mountain ash 
Yellow birch 


66 
52 
63 
74 


59 
31 
44 
61 




7 
21 
19 
13 


3 
27 
30 




1 
3 
6 


Four trees 
combined 


100 


— 




— 


— 




— 



140 



the bark greatly reduce the ability of lichens both to colonize and to 
persist on red spruce as compared to their ability to live on the bark of 
Fraser fir (Dey, 1978). Virtually all non-rare macrolichens which occur on 
spruce also occur with equal or greater frequency on fir with the exception 
of Parmeliopsis aleurites (Ach.) Nyl. and Pseudevernia consocians (Vain.) 
Hale & Culb., two species also common at lower elevations in the southern 
Appalachians on pine ( Pinus spp.) trees. Some of the 67 macrolichen species 
occurring on spruce and fir trees are found more frequently growing on 
deciduous trees such as mountain ash and yellow birch. Of the 100 
corticolous macrolichens epiphytic on the four tree species, 33 species occur 
only on the mountain ash and/or yellow birch trees. Therefore, a significant 
portion of the epiphytic macrolichen lichens in the southern Appalachian 
spruce-fir forest grow chiefly on the scattered deciduous trees in the 
forest. 

In contrast to numbers of macrolichens per tree species, examination of 
Tables 2 and 3 show that only 12 of the 100 corticolous species are strongly 
restricted (over 90% of collected specimens) to spruce-fir forest communities 
and an additional 11 species are mainly restricted (over 90% of collected 
specimens) to spruce-fir forest and successional fire cherry communities. 

Table 2. Macrolichen species in which 90% or more of the specimens collected 
in the southern Appalachian high-mountain areas were collected in 
the spruce-fir forest 



Alectoria fallacina Mot. 
Bryoria nadvornikiana (Gyeln.) 

Brodo & Hawksw. 
B. tenuis (Dahl.) Brodo & 

Hawksw. 
B. trichodes var. americana 

(Mot.) Brodo & Hawksw. 
Hypogymnia vittata (Ach.) Gas. 



Hypotrachyna croceopustulata 

(Kurok.) Hale 
H_. densirhizinata (Kurok.) Hale 
H. imbricatula (Zahlbr.) Hale 
H_. laevigata (Sm.) Hale 
H. oostingii (Dey) Hale 
H_. producta Hale 
H_. prolongata (Kurok.) Hale 



Table 3. Macrolichen species in which 90% or more of the specimens collected 
in the southern Appalachian high-mountain areas were collected in 
the spruce-fir forest and fire cherry communities (when taken 
together , not either by itself ) 



Bryoria bicolor (Ehrh.) Brodo & 

Hawksw. 
Hypotachyna gondylophora (Hale) 

Hale 
H_. thysanota (Kurok. ) Hale 
H. virginica (Hale) Hale 
Menegazzia terebrata (Hof fm. ) 

Mass. 



Parmelia saxatilis (L. ) Ach. 
P armelina dissecta (Nyl.) Hale 
Platismatia glauca (L.) Culb. & 

Culb. 
Pseudevernia cladonia (Tuck. ) 

Hale & Culb. 
Usnea confusa Asah. 
U. trichodea Ach. 



141 



Most of these species are found predominantly on the coniferous spruce and 
fir trees, but some are not infrequently also collected off deciduous trees 
and rock. Ramseur (1960) has estimated that together the spruce-fir forest 
and fire cherry communities occupy 90% of the total area of the southern 
Appalachian high-mountain areas. See Dey (1978) for a discussion of other 
lichen-vascular plant community relationships in the high-mountain areas. 

Table 4 summarizes the substrate relationships of the macrolichens in 
the southern Appalachian high-mountain areas. Having already discussed the 
corticolous species with emphasis on species occurring in the spruce-fir 
forest, it is interesting to note that of the terricolous and lignicolous 
species only Cladonia gracilis (L.) Willd. and C_. digitata (L.) Hoffm. are 
restricted to the spruce-fir forest. Similarly, of the saxicolous species 

Table 4. Numbers of macrolichen species on various substrates in the 
high-mountain areas above 1676 m i£ the southern Appalachians 



Substrate 



Number of species 



Coniferous trees 

Conifer trees only 

Conifer and deciduous trees 

Conifer and deciduous trees and rock ( - wood - soil) 

Conifer trees and rock ( - wood and soil) 
Deciduous trees 

Deciduous trees only 

Deciduous and conifer trees 

Deciduous and conifer trees and rock ( - wood - soil) 

Deciduous trees and rock ( - soil - wood) 
All trees 
Rock 



62 



Rock only 

Rock and trees ( - soil 

Rock and soil 

Rock and wood (- soil) 



wood) 



Soil 



Soil only 

Soil and rock ( - wood) 

Soil, rock and trees (- wood) 

Soil and wood 
Wood (rotting logs and stumps primarily) 

Wood only 

Wood and rock or soil 

Wood, rock and trees ( -soil) 

Wood, rock and soil 
All substrates 



5 
15 
37 

5 

no 

15 
37 
17 



27 

37 

8 

7 

10 

14 

12 

3 

4 

4 

21 

6 



109 



119 
99 



39 



35 



178 



Recognized by Dey (1978) and collected off substrate(s) at least twice (or 
once if less than ten total collections of the species were taken from all 
substrates in southern Appalachian high-mountain areas) 



142 



Baeomyces rufus (Huds.) Rebent. is the only species characteristically 
growing on small shady rocks within the spruce-fir forest proper while the 
other common saxicolous species -- Umbilicaria spp., Lasallia spp., 
Xanthoparmelia spp., Stereocaulon spp., and Parmelia stygia (L.) Ach. — are 
found on rock outcrops within a variety of vascular plant communities. 

Macrolichen species diversity within high-mountain areas 

Specimens cited in Dey (1975) provide information concerning macrolichen 
species diversity within the various southern Appalachian high-mountain areas 
above 1676 m (Table 5). Except for the smallest high-mountain areas, the 
decrease in macrolichen species diversity is positively correlated with the 
decreasing size of the various high-mountain areas. For the seven largest 
areas, the species-area curve, when both are plotted on log scales, is a 
straight line with a slope (Z) of 0.14 (r = 0.98). If data for all ten 
high-mountain areas are plotted, the regression line has a lower slope (Z = 
0.12 with r = 0.86). The decrease in macrolichen species diversity also 
reflects decreasing habitat diversity within the individual high-mountain 
areas as measured by the number of vascular plant communities recognized by 
Ramseur (1960) for each high-mountain area (Table 5). Grandfather Mt. and 
Mt. Pisgah are the two exceptions. These two high-mountain areas have 
greater macrolichen species diversities than either Mt. Rogers or White Top 
Mt., two areas with equal or greater numbers of vascular plant communities 
than the former. Perhaps the greater areas of exposed rock and rock outcrops 
available for saxicolous lichens on Grandfather Mt. and Mt. Pisgah account 
for their high species diversities. 

Table 5. Macrolichen species diversity within the high-mountain areas above 
1676 m ijn the southern Appalachians 



High- 
mountain 
area 





Vascular 


plants 


Macrolichens 


Size of 
area (km ) 


(Ramseur 


', 1960) 


(Dey, 1978) 




No. 






above 


No. 


community 


No. 


1676 m 


spp. 


typ 


es 


spp. 


49.0 


194 




8 


149 


29.4 


244 




8 


139 


24.8 


130 




8 


129 


8.8 


105 




6 


119 


5.7 


100 




6 


99 


2.0 


98 




5 


91 


1.1 


58 




3 


87 


0.4 


43 




3 


48 


0.05 


114 




2 


78 


0.03 


76 




4 


60 



Great Smoky Mts, 
Balsam Mts. 
Black Mts. 
Roan Mt. 
Plott Balsams 
Great Craggies 
Grandfather Mt. 
Mt. Rogers 
Mt. Pisgah 
White Top Mt. 



Totals 



121.1 



366 



178 



143 



For macrolichens the southern Appalachian high-mountain areas above 1676 
m, which includes most of the spruce-fir forest stands of the region, can not 
be considered continental habitat islands which are effectively isolated from 
one another. Many of the macrolichen species found in high-mountain areas 
have continuous distributions at lower elevations in the mountains. Besides 
many terricolous and saxicolous species, this includes many corticolous 
species which grow on a combination of deciduous tree species whose 
overlapping elevational ranges extend upward from low-elevation deciduous 
forests up into the high-elevation spruce-fir and deciduous tree forests. 
Thus, it is not surprising that the Z values of the macrolichen species-area 
curves given above fall within the normal range of Z values of 0.12 to 0.17 
reported for areas of continental mainland (Gorman, 1979). This is in sharp 
contrast to the relationship between the numbers of vascular plant species in 
the various high-mountain areas reported by Ramseur in 1960 (Table 5) and the 
sizes of the high-mountain areas. The Z values of the species-area curves 
using data from the seven largest areas is 0.30 (r = 0.89) and using data 
from the eight largest areas is 0.31 (r = 0.9^). Both of these Z values fall 
within the reported range of Z values (0.24 to 0.3*O for real islands and 
continental habitat islands (Gorman, 1979). Therefore, the eight largest 
areas of the southern Apalachian high-mountain areas can be considered to be 
continental habitat islands for vascular plants but not for macrolichens. 
Interestingly, the numbers of species of both macrolichens and vascular 
plants in the three smallest high-mountain areas — Mt. Rogers, Mt. Pisgah and 
White Top Mt. — are negatively correlated with the sizes of the areas with 
regression lines of slope (Z) -0.12 (r = -0.70) and of slope -0.27 (r = 
-0.78) respectively. 



Geographic relationships 

Seven of the 178 macrolichen species recognized by Dey in 1978 are 
narrowly endemic to the Appalachian Mountains. Five other species found in 
the high-mountain areas are essentially Appalachian in distribution but range 
into the adjacent Great Lakes region. Of these endemics only Alectoria 
fallacina Mot. and Hypotrachyna virginica (Hale) Hale are among the 
corticolous species collected over 90% of the time from spruce-fir forest 
only or from spruce-fir forests and fire cherry communities. Another 18 
species are known in North America north of Mexico only in the Appalachians, 
but have disjunctive representatives in other countries or continents (Dey, 
1978). Since the montane southern Appalachian spruce-fir forests have 
geographic affinities with the northern boreal coniferous forests, it is not 
surprising that the northern floristic element is well represented in the 
lichen flora. It should be noted, moreover, that many of the northern 
species are not restricted in their southern Appalachian distributions to the 
spruce-fir forests and often occur with equal frequency in other community 
types both at higher and lower elevations in the mountains. While many of 
the species with southern or tropical affinities also have broad 
distributions at both lower and higher elevations in the mountains and in 
surrounding low lands, there is a group of Hypotrachyna species — H. 
croceopustulata , H. densirhizinata , H. gondylophora , H. imbricatula , H. 
oostingii , H. producta , H. prolongata , H. rockii (Zahlbr.) Hale, and H_. 
thysanota — which are particularly interesting and restricted locally to the 



144 



spruce-fir forest and successional fire cherry communities at high 
elevations. These nine Hypotrachyna species are known in North America north 
of Mexico only in the southern Appalachian high-mountain areas, and they have 
disjunctive representatives in tropical America or in South America and/or 
Africa (Dey, 1979). Other interesting disjuncts in the high-mountain areas, 
but not necessarily organisms of the spruce-fir forest or restricted to the 
high-mountain areas in the southern Appalachians, include Anzia americana 
Yosh. & Sharp, Hypotrachyna sinuosa (Sm. ) Hale, Pseudevernia cladonia (Tuck.) 
Hale & Culb., Stereocaulon microcarpum Mull. Arg. [= S. ramulosum (Sw.) 
Rausch. in Dey, 1979 ] , S. tennesseense Magn., Sticta limbata (Sm. ) Ach., 
Umbilicaria caroliniana Tuck., and Xanthoparmelia incurva (Pers.) Hale. See 
Dey (1976 & 1979) for the distribution patterns of these and other 
interesting southern Appalachian macrolichens. 

THREATS TO THE LICHENS OF THE SPRUCE-FIR ECOSYSTEM 

Balsam woolly aphid 

The balsam woolly aphid has replaced fire and logging as the most 
destructive force threatening the southern Appalachian spruce-fir forest. 
The ongoing destruction of the Fraser fir trees by the aphid may have serious 
affects on the corticolous lichen flora of the southern Appalachian 
spruce-fir forest and particularly some of the noteworthy disjunctive 
Hypotrachyna species listed previously. All of these species are most 
readily collected off Fraser fir (except H. producta collected locally only 
once and then off a spruce tree), usually infrequently to rarely off spruce, 
and for some species rarely or apparently not at all off either deciduous 
trees or rocks. Some of these species may be vulnerable for local extinction 
as the balsam woolly aphid destroys their most preferred substrate tree (Dey, 
197^). Besides the destruction of the substrate fir trees, the microclimatic 
changes resulting from the opening up of the canopy as the fir trees die may 
have deleterious effects on a lichen's growth rate, reproductive rate, 
thallus persistence, and ability to colonize substrates. Such microclimatic 
changes may thus affect the ability of various lichen species to effectively 
utilize the remaining spruce trees as a substrate and possibly may even 
affect the future of the remaining spruce trees in some areas by affecting 
spruce reproduction and/or disease resistance. There are numerous questions 
which might be asked about how the balsam woolly aphid will indirectly affect 
the ecology of the local lichens of the spruce-fir forest. 

Air pollution 

Species of lichens are well known to be differentially sensitive to 
various air pollutants such as oxidants, sulfur dioxide, hydrogen flouride 
and trace elements, with a few species being very tolerant and others being 
at least as sensitive (if not more sensitive) to air pollution as the most 
sensitive higher plants (Nash, 1976; Nash and Sigal, 1980). Contrasting some 
of the results of Degelius (1941) with those of Dey (1978), it appears likely 
that air pollution may be responsibile for some changes in the macrolichen 
flora of the spruce-fir forest during the past 35 years. For example, 
Degelius indicates small, sterile specimens of Erioderma mollissimum (Samp.) 
DuRietz were found on mountain ash and Fraser fir trees in the spruce-fir 



145 



forest, but I did not find any during my collecting in the spruce-fir forest 
(the species is still rarely collected at lower elevations in the Great Smoky 
Mountains). More striking was the remarkable decrease in thallus size and 
fertility seen in my collections of the lichen Sticta fuliginosa (Dicks.) 
Ach. in the early 1970's compared to Degelius' collections in 1939 (Dey, 
unpublished). Reduction in luxuriance (i.e., cover and size of specimens) 
and fertility (i.e., frequency of production of ascocarps) are common 
symptoms in macrolichens and microlichens sensitive to air pollutants before 
the specimens are eliminated altogether from a polluted area (Hawksworth, 
Rose and Coppins, 1973). Studies on the interactions of lichens and air 
pollutants are currently an area of intense investigation worldwide (Ferry, 
Baddeley and Hawksworth, 1973; Nash and Sigal, 1980). 

AREAS WHERE MORE INFORMATION IS NEEDED 

Although the composition and geographic relationships of the macrolichen 
flora of the southern Appalachian spruce-fir forests are known, there are 
many areas where further information is needed to allow us to better 
understand the total lichen flora and its local ecology as follows: 

1 ) Microlichen flora 

A comprehensive floristic study of the crustose lichens of the southern 
Appalachian spruce-fir forest and other community types in the high-mountain 
areas is needed. The catalog of lichens from the State of Tennessee prepared 
by Skorepa (1972) and the initial study of Degelius (1941) will be helpful to 
anyone beginning a study of these crustose lichens. 

2) Quantitative sampling and analysis of the lichen vegetation 

In order to make empirical statements about the lichen vegetation, 
lichen communities, and ecological processes involving lichens within the 
spruce-fir ecosystem, quantitative studies must be undertaken and analyzed. 
Except for the corticolous lichens in the tree canopy, the lichen vegetation 
is sparse in most closed canopied spruce-fir forest stands growing on broad 
rounded mountain tops and gentle slopes, the sites best suited for the 
development of the forest. Therefore, to obtain a true appreciation of the 
importance of the lichens in the spruce-fir forest, it is also necessary to 
sample the forest on poorer sites such as along narrow ridge tops and steep 
slopes. Here the forest is poorly developed; the canopy is more open, but 
the lichen vegetation is more luxuriant. In any case, lichen biomass and 
primary productivity are likely to be very small or insignificant compared to 
that of higher plants, but the lichens may not be insignificant. 

3) Role of lichens in local mineral cycling 

In some ecosystems lichens are important in mineral cycling. Not only 
do they have the ability to alter precipitation chemistry (Lang, Reiners and 
Heier, 1976), but those lichens containing blue-green algae also have the 
ability to fix atmospheric nitrogen (Nash and Sigal, 1980). For example, 
Pike (1978) studied three ecosystems, comparing Douglas fir [ Pseudotsuga 
menziesii (Mirb.) Franco], balsam fir [ Abies balsamea (L.) Mill.] and Oregon 



146 



Oak ( Quercus garryana Dougl. ) woodland ecosystems, and found that epiphytic 
lichens seldom accounted for more than 10$ of the annual, above-ground 
turnover of minerals. According to him, lichens were relatively more 
important in the cycling of N than of P and K and of least importance in the 
cycling of Ca and Mg. The only study of mineral cycling by lichens in the 
southern Appalachian forests was conducted by Becker (1980) who studied 
nitrogen fixation by lichens. In his sampling of two southern Appalachian 
spruce forests, the few nitrogen-fixing lichens he encountered grew only on 
the relatively few deciduous trees in these forests and not on the conifers. 
He concluded that nitrogen fixation by lichens in the spruce forests of the 
southern Appalachians was very insignificant. Systems ecologists will have 
to decide whether or not further analysis of mineral cycling would be 
worthwhile. 

4) Effects of air pollution and the utilization of lichens as biomonitors of 
air pollution 

The need for studies to determine the effects of air pollution on the 
lichen flora of the southern Appalachians has already been mentioned. 

Lichens are useful as biomonitors of air pollution, and they should be 
used to document the magnitude of the air pollution problems in the southern 
Appalachians. Recognition of the fact that lichens could be useful as 
biomonitors comes from field observations of the differential sensitivity of 
species of lichens to various air pollutants, from laboratory studies in 
which a similar degree of differential sensitivity of the species to specific 
pollutants was confirmed, and from field studies documenting lichen recovery 
in areas following pollution abatement (Nash and Sigal, 1980). Examples of 
lichen recovery include the fairly rapid reinvasion of Lecanora muralis 
(Schreb. ) Rabenh. into an urban area in southern England following a 
reduction of atmospheric sulfur dioxide (Seaward, 1976) and recolonization by 
Pseudoparmelia caperata (L.) Hale into areas around a coal-fired generating 
power plant in Ohio within four years of the installation of tall emission 
stacks allowing a more rapid dispersal of sulfur dioxide from the plant site 
(Showman, 1981). Baseline studies to determine which sensitive lichens 
should be used as biomonitoring organisms in the southern Appalachians should 
be undertaken now. 

While lichens have been shown to be too effective at accumulating lead 
to be useful in monitoring lead deposition from vehicular exhaust along 
highways (Laaksovirta, Olkkonen and Alakuijala, 1976), Lawrey and Hale (1981) 
in a retrospective study of lichen lead accumulation in the northeastern 
United States concluded that lichens may be useful in monitoring long term 
increases in background Pb levels due to large-scale atmospheric transport. 
Perhaps a similar study in the southern Appalachians would provide useful 
information complementary to the ongoing study of lead levels in the 
vegetation litter and soils of the spruce-fir forest in the Great Smoky 
Mountain National Park being conducted by R. Turner and M. Bogle of the 
Oak Ridge National Laboratories, Oak Ridge, Tennessee. 



147 



5) Effects of the balsam woolly aphid 

The need to monitor responses of the lichens to the environmental 
changes induced directly or indirectly by the death of Fraser fir trees 
infested with balsam woolly aphids is clear and timely. Such a study could 
complement ecological studies of vascular plant succession due to aphid 
damage. 

6) Lichen-invertebrate associations 

When one collects fruticose and foliose lichens, one readily becomes 
impressed with the abundance and diversity of insects and other invertebrates 
that one uncovers or inadvertantly collects with the specimens. Lichens 
serve as a protective environment for invertebrates as places for 
concealment, as sources of camouflage, and as objects to be mimicked. For 
example, Skorepa and Sharp (1971) report that the larvae of the lacewing 
Nodita pavida (Chrysopidae) in the southern Appalachians construct and carry 
trash packets consisting solely of lichens presumably as camouflage for 
themselves. The movement of these larvae may be a method of dispersal for 
the lichens. Invertebrate feeding on lichens, the resistance of some lichens 
to invertebrate feeding, and the recognition of invertebrate-lichen 
communities in the southern Appalachian spruce-fir ecosystem are also worthy 
of study. Gerson and Seaward (1977) have reviewed much of the worldwide work 
on lichen-invertebrate associations. Since such studies would require 
specialists to identify the insects and other invertebrates and would be very 
time consuming, it may be unrealistic to expect that a high priority will be 
given to these studies by entomologists and other specialists. 



While more information in all of these areas would enable us to obtain a 
better understanding of the lichens in the southern Appalachian spruce-fir 
ecosystem, it is suggested that the following studies should be given 
priority: 1) quantitative studies of the lichen vegetation, 2) studies of 
the ramifying effects of the balsam woolly aphid on the lichen flora and 
vegetation, 3) studies of air pollution effects in the southern Appalachians 
utilizing lichens as biomonitors of the magnitude of local pollution problems 
in conjunction with other ongoing studies of air pollution in the region, and 
4) further study to inventory the crustose lichens of the area. 



LITERATURE CITED 

Becker, V.E. 1908. Nitrogen fixing lichens in forests of the southern 
Appalachian Mountains of North Carolina. Bryologist 83: 29-39. 

Degelius, G. 19^1. Contributions to the lichen flora of North America. II 
The lichen flora of the Great Smoky Mountains. Ark. Bot. 30A(3): 1-80. 



148 



Dey, J. P. 197^. New and little known species of Parmelia (lichens) in the 
Southern Appalachian Mountains. Castanea 39: 360-369. 

. 1975. The Fruticose and Foliose Lichens of the High-Mountain 

Areas of the Southern Appalachians. Ph.D. Dissertation, Duke University, 
Durham, N.C. 

. 1976. Phytogeographic relationships of the fruticose and foliose 



lichens of the southern Appalachian Mountains, p. 398-416. Li B.C. Parker 
and M.K. Roane, eds. The Distributional History of the Biota of the 
Southern Appalachians. Part IV. Algae and Fungi. Virginia Poly. Inst. & 
State Univ., Res. Div. Monogr. 

_. 1978. Fruticose and foliose lichens of the high-mountain areas of 
the southern Appalachians. Bryologist 81: 1-93. 

1979. Notes of the fruticose and foliose lichen flora of North 



Carolina and adjacent mountainous areas. Veroff. Geobot. Inst. ETH, 
Stiftung Rubel, Zurich 68: 185-205. 

Ferry, B.W., M.S. Baddeley and D.L. Hawksworth, eds. 1973. Air pollution 
and lichens. Athlone Press, London. 

Gerson, U., and M.R.D. Seaward. 1977. Lichen-invertebrate associations, 

p. 69-119. Ill M.R.D. Seaward, ed. Lichen ecology. Academic Press, Inc., 
London. 

Gorman, M. 1979. Island ecology. Chapman and Hall (Publishers) Ltd., 
London. 

Hawksworth, D.L., F. Rose and B.J. Coppins. 1973. Changes in the lichen 

flora of England and Wales attributable to pollution of the air by sulfur 
dioxide, p. 330-367. ln_ B.W. Ferry, M.S. Baddeley and D.L. Hawksworth, 
eds. Air pollution and lichens. Athlone Press, London. 

Laaksovirta, K., H. Olkkonen and P. Alakuijala. 1976. Observations of the 
lead content of lichen and bark adjacent to a highway in southern Finland. 
Environ. Pollut. 11: 247-255. 

Lang, G.E., W.A. Reiners and R.K. Heier. 1976. Potential alteration of 

precipitation chemistry by epiphytic lichens. Oecologia (Berl.) 25: 
229-241. 

Lawrey, J.D., and M.E. Hale, Jr. 1981. Retrospective study of lichen lead 
accumulation in the northeastern United States. Bryologist 84: 449-456. 

Moore, B.J. 1963. A Preliminary Annotated Checklist of the Foliose and 

Fruticose Lichens in the Great Smoky Mountains National Park. M.S. 
Thesis, The University of Tennessee, Knoxville. 



149 



Nash, T.H., III. 1976. Lichens as indicators of air pollution. 
Die Naturwissenschaften 63: 364-367. 

, and L.L. Sigal. 1980. Sensitivity of lichens to air pollution 



with an emphasis on oxidant air pollutants, p. 117-124. In_ P.R. Miller, 
tech. coordinator. Proceedings of the symposium on effects of air 
pollutants on Mediterranean and temperate forest ecosystems, June 22-27, 
1980, Riverside, California, U.S.A. Pacific Southwest Forest and Range 
Exp. Stn., Forest Serv. Gen. Tech. Rep. PSW-43, U.S. Dep. Agric, 
Berkeley, Calif. 

Perry, J.D., and B.J. Moore. 1969. Preliminary check list of foliose and 
fruticose lichens in Buncombe County, North Carolina. Castanea 34: 
146-157. 

Ramseur, G.S. 1960. The vascular flora of high mountain communities of 
the southern Appalachians. Jour. Elisha Mitchell Sci. Soc. 76: 82-112. 

Seaward, M.R.D. 1976. Performance of Lecanora muralis in an urban 

environment, p. 323-357. In D.H. Brown, D.L. Hawksworth and R.H. Bailey, 
eds. Lichenology: progress and problems. Academic Press, Inc., London. 

Showman, R.E. 1981. Lichen recolonization following air quality 
improvement. Bryologist 84: 492-497. 

Skorepa, A.C. 1972. A catalog of the lichens reported from Tennessee. 
Bryologist 75: 481-500. 

, and A.J. Sharp. 1971. Lichens in "Packets" of lacewing larvae 



(Chrysopidae). Bryologist 74: 363-364. 



150 



COMMENTS ON THE FUNGI OF THE SPRUCE-FIR FOREST 
OF THE SOUTHERN APPALACHIAN MOUNTAINS 



Ronald H. Petersen' 

Abstract - The identities and distribution patterns of fungi occurring 
in the spruce-fir forest are imperfectly known, for research has not 
emphasized this ecological niche. Potential major research projects 
are identified. 

It may be safely stated that no concerted research effort presently is underway 
on the fungi of the spruce-fir forest of the Great Smoky Mountains National Park. 
Two pre-doctoral projects are progressing, one at Virginia Polytechnic Institute (Mr. 
Gerald Bills) on the mushrooms (Agaricales) of selected spruce-fir forest sites in 
West Virginia, the other at the University of Tennessee (Mr. Hack Sung-Jung) on 
the taxonomy of the Basidiomycetes decaying spruce and fir wood in the Park. 
Other research efforts on the fungi of this forest type, while perhaps applicable to 
conditions within the range in question, are not being carried out nearby, and will 
be mentioned below. 

Traditionally, the amount of research has been directly proportional to the 
number of researchers in the area. In this case, the University of Tennessee has had 
a mycologist in residence for nearly 70 years, but while those individuals have 
produced significant monographs of various fungal groups over the years, they have 
not concentrated on a particular ecological niche. Of the surrounding institutions, 
few have had a mycologist, and when such people were present, their research took 
them in other directions. 

As most research on fungi of an ecotype, efforts on the spruce-fir forest may 
be divided into two categories: I). Inventory and taxonomy, and 2). Ecology. 

INVENTORY AND TAXONOMY: 

Any effort to compile floristic profiles of the fungi of this forest type is bound 
to be hampered by the inaccessibility of all stands of spruce and fir. Even within 
the Park, several such stands are almost a full day's hike from the nearest road, 
making collecting difficult. In the many years of mycologizing in the Smokies by 
Hesler, he did not visit most of the spruce-fir sites, considering them remote and 
relatively unprofitable. Only the areas on Clingman's Dome and adjacent to Newfound 
Gap saw frequent visits, and even on those occasions only mushrooms were gathered. 

Until the two dissertation projects mentioned above were undertaken, no floristic 
treatment of fungi of this forest type has been undertaken. The best information 
has resided in scattered monographic treatments of various groups of fungi, or 
floristic treaatments of wider areaas. A prime example is the "Checklist of Fungi 
for the Great Smoky Mountains National Park" originally compiled by L.R. Hesler, 



' Botany Department, University of Tennessee, Knoxville, TN 37916 

151 



and lately revised and edited by R.H. Petersen . In that document, about 

1700 species of fungi were listed, of which about I 150 were mushrooms, an incredibly 
rich flora for an area of this size. Nonetheless, no break-down of forest type, 
elevation or other subunits was attempted, and it is necessary to check individual 
herbarium specimens to ascertain their collection sites. Likewise, monographs of 
various agaric (mushroom) genera, though written or co-authored from the University 
of Tennessee, and based on many collections from the Smokies, have little or no 
disbributional data explicitly stated, and again individual collections must be traced 
for more accurate information. Such a task is so formidable as to be prohibitive. 
Instead, it may be more efficacious to start over again in the spruce-fir forests, 
exactly the concept which has prompted the two dissertations cited above. 

This does not mean that no statement can be made concerning these fungi, but 
merely that accurate, inclusive information is lacking. The fungi found in this 
forest type may be divided into three categories, much as any fungus flora: I) 
parasites; 2) decay orgnaisms; and 3) mycorrhizal associates. 

Parasites: To my knowledge, no catastrophic or serious fungus parasites have 
been identified on these trees. There is no reason to suppose that a counterpart to 
the Pine Blister Rust or Chestnut Blight is about to befall the spruce-fir forest, 
although the Balsam Wooly Aphid is catastrophic enough. When found, parasites 
seem centered in the Loculoascomycetes, as might be expected from research in 
northern Europe. 

Decay Organisms: It must be emphasized that virtually all of the taxonomy of 
decay organisms of spruce and fir biomass has been based on fruitbodies of those 
fungi. Thus, while a number of taxa could be identified as occurring on these 
substrates, many other fungi may grow there, but may be inhibited for fruiting for 
a variety of reasons, and therefore may escape the inventories thus far compiled. 
While no profile for such organisms has been drawn up for the spruce-fir forest, 
certain conclusions can be drawn. First; there are a few conspicuous fungi which 
fruit in such profusion as to be obvious to anyone walking through the forest. The 
brilliant yellow cups of Helotium citrinum fit this category, for example, as do the 
similar structures of Dasyscypha agasizzii. In the late summer, the bright rusty 
red mushroom Pholiota kauffmanii stands out on rotting logs. Second; the number 
of such decay fungi is surely much higher than ever predicted, with the unreported 
taxa to come largely from small or inconspicuously fruiting types. The jelly fungi, 
for example, have never been inventoried, but will yield several taxa, among which 
will be some new to science. Third; of those already identified, there is a definite, 
significant "northern" element not found at lower altitudes. Whether these fungi 
are limited to spruce and fir wood is open to question, but they fruit only at the 
tops of the mountains. Thus, as in other organismal groups, one can identify a 
circum-boreal flora which extends down the Appalachain chain to the mountaintops 
in the Park. 

Mycorrhizal Associations: Aside from general conclusions on mycorrhizal 
symbionts based on observations of tree species found in the vicinity of fungus 
collections, little has been done to systematically identify the fungi associated with 
spruce and fir. Currently, as part of the VPI project, such pure-culture syntheses 
are being established, but in many cases, the fungal component does not culture 
well, and is difficult, therefore, to grow in a condition from which to make the 
aseptic synthesis. 



152 



Field observations would seem to indicate that the genera Russula, Lactarius, 
Amanita , and Cortinarius are among the most common mycorrhizal symbionts. Of 
these, the first three genera have been treated in alpha taxonomic monographic 
works. The latter is by far the largest (perhaps a thousand species in North America), 
and will be the most difficult to bring to order. Several other genera are represented 
in putative mycorrhizal associations, but the lack of emphatic collecting in these 
high-altitude forests has resulted in only superficial knowledge of the fungus flora as 
a whole. 

ECOLOGY 

As might be inferred from the paragraph above on mycorrhizal fungi, rather 
little can be said about the ecology of these fungi if their identities remain unknown 
or confused. Experiments with reproducible results are based on correct identification 
of the organisms involved. Nonetheless, the following studies seem to hold high 
potential for the future. 

Inventory and experimentation within the spruce-fir forest: The first order of 
business in the concerted inventorying of this same time, modern techniques can be 
applied to synthesize axenic mycorrhizal associations under laboratory conditions. 
In such a way, at least the dominant associations may be identified. 

Interface between spruce-fir forest and Beech Gaps: In the Smoky Mountains 
(at least), many of the saddles along the ridge and associated peaks show a markedly 
different forest type, dominated by Fagus sometimes mixed with Betula. While the 
causes of this abrupt change in forest type may be largely edaphic, it has been 
proposed that the change in forest type may be accompanied by, or caused by, a 
concommitant change in mycorrhizal symbionts. A study of the fungi fruiting in 
the Beech Gaps (following the inventory of fungi of the spruce-fir forest) would 
give an inventory of those areas. This may lead to isolations from soil samples 
across transects traversing both forests in an attempt to sample the change in fungal 
components. 

Equally interesting would be similar studies on the grassy balds and their interface 
with the spruce-fir forest. The grassy balds do not appear to be stable, however, 
so the same barriers to colonizaton by the spruce and fir apparently do not exist 
as they do in the Beech Gap situation. 

Decay of spruce and fir biomass: The Balsam Wooly Aphid is about to cause 
the demise of fir in these forests. The natural sequence of events will be the 
defoliation of the trees, followed by pruning of the boughs, and finally the fall of 
the trunk. Each step will add significantly more biomass to the forest floor than 
has been the case for the recorded past. At the same time, a fungus "bloom" can 
be anticipated at each step of the way, although perhaps not visible to the casual 
observer. The catastrophe presents an ideal opportunity to chronicle this sequence 
of fungal invasions, and on the longer term, to sample downed fir logs over a period 
of years in order to eludicate the sequence of fungal fruiting and permeation of 
the wood. 

Acid rain: In the past decade or two, serious decline in growth of high-elevation 
coniferous trees has been noted. While acid rain is suspected as the cause, or at 



153 



least as a significant factor, it is not known whether such conditions operate directly 
on the tree, or whether the tree is affected because of a decline in its mycorrhizal 
symbionts. Work at the University of Vermont and elsewhere is attempting to 
clarify this situation, but research is still very young. Because the Smoky Mountains 
are exposed to significant amounts of acid rain, they make an ideal laboratory in 
which to study the phenomenon and its ramifications. Because of their mycorrhizal 
role, the fungi will become pivotal in such studies. 



154 



HERPETOFAUNA OF THE SPRUCE-FIR ECOSYSTEM IN THE SOUTHERN 
APPALACHIAN MOUNTAIN REGIONS, WITH EMPHASIS ON THE GREAT 
SMOKY MOUNTAINS NATIONAL PARK 

Raymond C. Mathews, Jr.l and Arthur C. Echternacht^ 



Abstract . The diversity of amphibians and reptiles in the topo- 
graphically complex region of the Southern Appalachian Mountains is 
high, especially with respect to salamanders. The salamander fauna 
is unmatched anywhere else in the world and the region has a long 
history of herpetof aunal study. Surprisingly, however, relatively 
little research has been centered in the spruce-fir ecosystem. The 
herpetofaunal diversity in the spruce-fir ecosystem of the Great 
Smoky Mountains National Park is less diverse than lower elevation 
ecosystems of the Park, but still includes 3 species of frogs, 13 
of salamanders and 8 snakes. Only two species, both salamanders, 
may be said to be characteristic of the spruce-fir ecosystem. 
These are the imitator salamander, Desmognathus imitator and the 
pygmy salamander, Desmognathus wrighti . The remainder of the 
species of amphibians and reptiles which occur in the spruce-fir 
ecosystem occur relatively widely in ecosystems at lower 
elevations. Resource management problems associated with 
herpetofauna in the spruce-fir forest include roadcuts through 
Anakeesta formations, acid precipitation effects, Balsam Wooly 
Aphid parasitism of Frasier Fir and subsequent loss of habitat, and 
European wild boar rooting. 

Additional Keywords : Salamanders, Frogs, Snakes, Anakeesta 
Formations, Acid Precipitation. 

INTRODUCTION 

Spruce-fir forest occur as isolated ecological islands in the southern 
Appalachian mountains of southwestern Virginia, western North Carolina, 
and east Tennessee. The diversity of amphibians and reptiles in the 
topograpically complex region which includes spruce-fir islands is high, 
especially with respect to salamanders. The salamander fauna is 
unmatched anywhere else in the world and the region has a long history 
of herpetofaunal study. Surprisingly, however, relatively little 
research has been centered in the spruce-fir ecosystem. It is the 
purpose of this paper to introduce the herpetofauna of the spruce-fir 



^Graduate Student, Graduate Program in Ecology, University of Tennessee, 
Knoxville, Tenn. 37996. Present address: Vice-President, Geo-Marine 
Inc., Engineering and Environmental Services, 1316 Fourteenth Street, 
Piano, Texas 75074. 

^Associate Professor, Department of Zoology and Graduate Program in 
Ecology, University of Tennessee, Knoxville, Tenn. 37996. 



155 



ecosystem, to comment on selected species, and to identify factors which 
threaten the herpetofaunal community. 

The Great Smoky Mountains National Park, with an area of only 2,072 
square kilometers, is home to 72 species of amphibians and reptiles. Of 
these, 35 are amphibians (12 frogs, 25 salamanders) and 35 are reptiles 
(6 turtles, 8 lizards, and 21 snakes). The magnitude of this diversity 
is evident when one considers that the State of Tennessee, with an area 
of 109,417 square kilometers , has a herpetofauna of 115 species, only 40 
percent more than are found in the Park. The herpetofaunal diversity in 
the spruce-fir ecosystem is less diverse, but still includes 3 species 
of frogs, 13 of salamanders and 8 snakes (Table 1). The herpetofaunal 
diversity of the spruce-fir ecosystem above 1650 m is further reduced to 
3 frog species, 10 salamanders and 4 snakes (Table 1). As advanced 
techniques of biochemical systematics are employed, additional species 
will no doubt be identified. Three species of salamanders which occur 
in the spruce-fir ecosystem have only recently been recognized as 
distinct on the basis of such techniques: Desmognathus imitator (Tilley 
et al. 1978), IK santeetlah (Tilley 1981), and Plethodon serratus 
(Highton and Webster 1976). 

SPRUCE-FIR HERPETOFAUNAL ENDEMICS 

Only two species, both salamanders, may be said to be characteristic of 
the spruce-fir ecosystem. These are the imitator salamander, 
Desmognathus imitator and the pygmy salamander, Desmognathus wrighti . 
The red-cheeked salamander, a unique color morph of the Appalachian 
woodland salamander, Plethodon jordani , is also characteristic of 
spruce-fir, but its limited distribution does not encompass the entire 
series of spruce-fir islands. 

Desmognathus imitator , many individuals of which have cheek patches 
which contrast in color to the generally dark coloration of the 
salamander, has been considered a Batesian mimic of the red-cheeked 
salamander with which it is sympatric (Huheey 1966, Orr 1968, Brodie and 
Howard 1973). The species is found in moist situations and is commonly 
encountered under rocks and under or in rotting logs. ' Its congener, J). 
wrighti , is one of the smallest of salamanders, reaching a maximum 
length of just over 2 inches. Desmognathus wrighti is the most 
terrestrial of its genus, having done away with the larval stage of its 
life cycle; eggs hatch directly into miniature adult-like salamanders. 
Like JD. imitator , the pygmy salamander favors moist areas but may be 
found relatively far from free-flowing or standing water. Both 
desraognathines are most active on cool, damp nights. On especially damp 
nights, following rains or when fog is present, _D. wrighti may be found 
on leaves some distance from the ground, and ID. imitator has been found 
several feet off the ground having climbed the rough bark of trees. 
Tilley and Harrison (1969) emphasized that, although I), wrighti is 
characteristic of the spruce-fir ecosystem, it is not restricted to 
ranges which presently support spruce-fir. They suggest that 
populations of the pygmy salamander found on mountains which lack 

156 



Table 1. Species of amphibians and reptiles known to range above 1305 m in the 
Great Smoky Mountains National Park. Species which range to above 1650 
m are indicated with an asterisk (*). 



Habitat Type 



Aquatic Terrestrial 



ANURA (Frogs) 

* Bufo americanus 
* Hyla crucifer 
* Hyla versicolor 

CAUDATA (Salamanders) 

* Desmognathus imitator 

Desmognathus monticola 
* Desmognathus ochrophaeus 
* Desmognathus quadramaculatus 
* Desmognathus santeetlah 
* Desmognathus wrighti 
* Leurognathus marmoratus 

Plethodon glutinosus 
* Plethodon jordani 

* Plethodon serratus 

* Gyrinophilus porphyriticus 

Pseudotriton ruber 
* Eurycea bislineata 

SERPENTES (Snakes) 

Nerodia sipedon 
* Storeria occipitomaculata 
* Thamnophis sirtalis 
* Diadophis punctatus 

Coluber constrictor 

Elaphe obsoleta 

Lampropeltis triangulum 
*Crotalus horridus 



American Toad 
Spring Peeper 
Gray Treefrog 



Imitator Salamander 
Seal Salamander 
Mountain Dusky Salamander 
Black-Bellied Salamander 
Santeetlah Salamander 
Pygmy Salamander 
Shovel-Nosed Salamander 
Slimy Salamander 
Appalachian Woodland 

Salamander 
Southern Red-Backed 

Salamander 
Spring Salamander 
Red Salamander 
Two-Lined Salamander 



Northern Watersnake 
Red-Bellied Snake 
Eastern Garter Snake 
Ringneck Snake 
Black Racer 
Black Rat Snake 
Milk Snake 
Timber Rattlesnake 



X 
X 



X 

X 
X 



X 
X 

X 

X 

X 

X 



X 
X 
X 
X 

X 
X 
X 



157 



spruce-fir are relicts of a time when spruce-fir occurred more widely in 
the southern Appalachians. 

Delcourt and Delcourt ( this volume ) have documented the withdrawal of 
spruce-fir forests over the period since the full-and late-glacial 
interval 18,000 YR BP to 12,500 YR BP. With gradual climatic 
amelioration, spruce-fir forests became disjunct and, at the period of 
peak warmth 8,000 YR to A, 000 YR BP, were finally restricted to high 
elevations in the southern Appalachians. It is by this mechanism that 
ancestral populations of Desmognathus wrighti became disjunct. The 
present extent of spruce-fir forest in the southern Appalachians is only 
about 120 km^ t a nd the range of _D. wrighti is correspondingly small. No 
detailed analyses of geographic variation in morphology or genetics of 
the pygmy salamander has been published, but as it becomes possible with 
increasing accuracy to determine the age of spruce-fir islands, the 
species should be valuable in studies aimed at assessing rates of 
evolutionary change. All populations are presently considered 
conspecific and no geographic variants (described subspecies or local 
morphs) have been identified. 

With the exceptions noted above, the remainder of the species of 
amphibians and reptiles which occur in the spruce-fir ecosystem occur 
relatively widely in ecosystems at lower elevations. Among these is the 
eastern garter snake, Thamnophis sirtalis . High-elevation populations 
of this species in the Great Smoky Mountains National Park tend toward 
melanism, adults having only faint dorsal stripes and dark brown overall 
coloration. This seems to be the only instance of a high elevation 
morph associated with any of the amphibians and reptiles of the 
spruce-fir ecosystem with the exception of that of Plethodon Jordani 
already mentioned. 

HIGH ELEVATION STREAM ASSOCIATED SALAMANDERS 

Due to the unique diversity of salamanders in the Southern Appalachian 
Mountain region, a great deal more research has been conducted on that 
element of the herpetofauna. High elevation (> 1200 m) stream 
associated salamanders (those that live in the stream and/or on the 
stream side) in the Great Smoky Mountains National Park occupying the 
virgin spruce-fir forest account for only about 17% of the overall 
abundance (Mathews 1984). The greatest abundance (63%) of such 
salamanders occur in the mesic type hemlock-hardwood cove forest. Other 
forest types produced lesser abundances of salamanders associated with 
stream environs: 14% in virgin mesic type mixed cove hardwoods, 3% in 
mature northern hardwoods (Gray Beech gap), 2% in second growth mesic 
type hemlock-hardwood cove forest, and 1% in virgin mesic type hardwood 
flats. Species commonly associated with streams in the spruce-fir 
forest are indicated in Table 1. The density of stream associated 
salamanders is less in high elevation areas of the Great Smoky Mountains 
National Park as indicated in Tables 2 and 3 (Mathews 1984). An 
explanation for this distribution is lacking at the present time, though 
the environmental extremes in temperature and precipiation encountered 



158 



Table 2. Number of sites with the indicated density of stream 

associated salamanders at different elevations in the Great 
Smoky Mountains National Park. 







Elevation 




ROW 


TOTAL 


NO. /HECTARE 


<600m 


1600m 


11200m 


FREQ.(%) 


< 50 


32 


31 


4 


67 


( 3.9) 


> 50 


66 


188 


20 


274 


(15.9) 


100 


66 


220 


13 


299 


(17.4) 


200 


73 


150 


14 


237 


(13.8) 


> 300 


70 


201 


11 


282 


(16.4) 


500 


50 


138 


23 


211 


(12.3) 


1000 


34 


179 


39 


252 


(14.7) 


2000 


32 


34 


11 


97 


( 5.6) 


COLUMN TOTAL 












FREQ. (%) 


423 (24.6) 


1141 (66.4) 


155 (9.0) 


1719 


(100) 



Table 3. Number of sites with the indicated biomass of stream 

associated salamanders at different elevations in the Great 
Smoky Mountains National Park. 

Elevation 



GRAM WT. /HECTARE 



<600m 



1600m 



>1200m 



ROW TOTAL 
FREQ.(%) 



< 


50 


> 


50 


> 


200 


> 


500 


> 


1000 


> 


3000 


COLUMN TOTAL 


FREQ. 


(%) 



71 
100 
80 
81 
55 
36 



106 
229 
293 
222 
183 
108 



8 
15 
53 
31 

8 
40 



185 
344 
426 
334 
246 
184 



(10.8) 
(20.0) 
(24.8) 
(19.4) 
(14.3) 
(10.7) 



423 (24.6) 1141 (66.4) 155 (9.0) 



1719 (100) 



159 



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160 



by salamanders at high elevations is presumed to account for much of 
this profile. 

Partial correlation analyses (Nie 1983) were used as a measure of 
association between stream salamander density and environmental 
parameters simultaneously examined while adjusting for the effects of 
one or more additional variables. The results of these analyses are 
given in Table 4. It is evident that no one environmental variable 
among those examined accounts for the density patterns of stream 
associated salamanders in the Park. The most important relationships 
influencing the number of species are air and water temperature, stream 
order, season, forest type, and elevation. Similarly for number per 
hectare it is watershed, logging history, stream pH, stream order, 
terrain slope, forest type, and elevation. Weight per hectare is most 
influenced by stream order, and terrain slope. The wet weight of 
salamanders is most influenced by forest type. Other partial 
correlations of importance which are not presented in Table 4 are the 
following: number per hectare with forest type controlling for stream 
nitrate (NO3) concentration = -.2249 (P<.001), number per hectare with 
elevation controlling for NO3 = .2603 (P<.001), number per hectare with 
forest type controlling for turbidity = -.2102 (P<.001), and number per 
hectare with elevation controlling for turbidity = .2485 (P<.001). 
Although we cannot explain by these analyses the reason for the 
influence on stream associated salamander density of these environmental 
variables, it is evident that the spruce-fir forest type has an effect 
on the observed pattern. 

RESOURCE MANAGEMENT PERSPECTIVE 

From a resource management perspective, the impacts on the herpetofauna 
of the spruce-fir zone in the Great Smoky Mountains National Park of 
greatest importance are as follows: 

(1) Roadcuts through Anakeesta Formations 

(2) Acid precipitation effects 

(3) Balsam Wooly Aphid parasitism of Frasier Fir 

(4) European wild boar rooting 

To these we add a fifth factor — a past research project which may have 
continuing effects on park distribution patterns: 

(5) Unauthorized collecting and associated habitat disturbance 

Road construction through Anakeesta Formations in the Park have had a 
serious effect on salamanders. The problem first became apparent when 
Huckabee et al. (1975) discovered that mortalities of native brook trout 
( Salvelinus fontinalis ) had occurred during the construction of U.S. 
Highway 441 in 1963 near Newfound Gap on the outer edge of the 
spruce-fir zone. Fish were reportedly eliminated for approximately 8 km 
below roadfill areas, and attempts to reestablish a fishery by stocking 
failed. Salamander mortality in Beech Flats stream below the roadcut 



161 



was attributed to acidic heavy metal leachate formed through redox 
processes associated with pyritic content of the Anakeesta roadfill 
bedrock (Mathews and Morgan 1982). Soluble aluminum in high 
concentrations is believed to be a major factor in the intoxication 
process. Observations of gill hyperplasia in the aquatic shovel-nosed 
salamander ( Leurognathus marmoratus ) were made in Beech Flat Creek as 
specimens intrained by the flow passed through the culvert under Highway 
441, from which they were exposed to Anakeesta leachate where death 
eventually ensued. An isolated population of stream dwelling 
salamanders thus appears to have resulted as a consequence of this 
barrier to stream migration. Although some possible forms of 
reclamation have been described through sodium hydroxide neutralization 
(Mathews et al. 1976), nothing has been done to alleviate this problem. 
The best advice appears to be to avoid roadcuts through Anakeesta 
Formations so that other streams may not be so impacted. 

Acid precipitation has been documented in Great Smoky Mountains National 
Park through the monitoring of pH levels as part of the National 
Atmospheric Deposition Program (Mathews et al. 1979, Mathews and Larson 
1980), and remote monitoring of depressed stream pH levels in 
experimental streams of the Park (Mathews 1980). Bioassay studies of pH 
depression effects on the shovel-nosed salamander ( Leurognathus 
marmoratus ) , suggest that some pH depressions presently occurring in 
Park streams are near acutely toxic levels for larval and subadult forms 
(Mathews and Larson 1980). The shallow acidic soils of the spruce-fir 
forest offer little buffering to acid rain, making that area a 
potentially high impact zone. Additionally, the coniferous forest is a 
poor scavenger of hydrogen ions in throughfall precipitation and the 
conifer needles breakdown more acidic than broadleaf deciduous leaves, 
compounding the acidic exposure to this type environ (Abrahamsen and 
Horntvedt 1976; Knabe and Gunther 1976; Scholz and Reck 1976). The 
potential effect of acidic deposition to the spruce-fir forest community 
should be an area of extensive investigation. 

The loss of the Frasier Fir forest in the Southern Appalachians through 
the attack of the Balsam Wooly Aphid is a threat which parallels the 
loss of the American Chestnut forest. Although the spruce-fir forest 
community has few endemic amphibians or reptiles, the few species 
already mentioned may also be lost as the Frasier-Fir forest community 
deteriorates. Resistance and/or susceptibility to biotic pathogens and 
parasites may be affected by acid precipitation and long term effects 
may be presently expected (Tamm and Cowling 1976), which may be related 
to the infestation of the Balsam Wooly Aphid on Frasier Fir in the 
Park. Since research has not been focused on the relationships of the 
herpetofauna to the spruce-fir zone, we will not comment further on this 
subject, except to emphasize the need to fill that gap in our knowledge. 

Since the European wild boar ( Sus scrofa ) was accidently introduced into 
the Great Smoky Mountains National Park, its population has expanded and 
presently occupies about three-quarters of the Park (Howe and Bratton 
1976, Howe et al. 1981). The hogs' rooting activity have severely 



162 



damaged the herbaceous understories of several types of forest, 
including the spruce-fir. Rooting occurs in the spruce-fir forest in 
the Park to a lesser extent than other forest types and usually occurs 
there during the hottest months of the year, likely associated with 
thermoregulatory response of the European wild hog to move into higher 
elevations (Belden and Pelton 1975). Scott and Pelton (1975) reported 
rooting in shallow stream beds as a possible attempt to obtain aquatic 
invertebrates. Where rooting in such streams has occurred, we have 
observed extensive disruption of substrate, sediments, and natural 
debris dams, with consequent high tubidity levels. Direct predation of 
some species is also attributable to the wild boar. They eat large 
quantities of invertebrates, including snails and crayfish, and a 
variety of amphibians, including the Appalachian woodland salamander 
( Plethodon jordani ) of which the red-cheeked morph is endemic to the 
Park (Singer and Ackerman 1981). Since P_. jordani exists in very dense 
but patchy populations in the spruce-fir and cove hardwood forests of 
the Park the effect of rooting on their habitat and direct foraging 
effects could pose a severe impact. Singer et al. (1982), however, 
reported no significant difference in salamander numbers between 
pristine and rooted stands (P>0.95), and only pygmy salamanders 
( Desmognathus wrighti ) significantly declined. Only surface ground 
dwelling salamanders were studied, however, so as to minimize collecting 
effects. Thus, the overall effect of rooting activity on the 
salamanders may not have been assessed. Salamanders may find adequate 
alternate habitats in rooted areas such as on vegetation (Hairston 
1949), in soil refugia (Taub 1961) and inside or under the larger logs 
that are not disturbed by wild boar. The disturbance by rooting appears 
to be long lasting, however, as we have observed rooted areas that 
remain disturbed for several years. Huff (1977) reported damaged areas 
in the Gray Beech forest of the Park had a substantial reduction in 
total plant cover, including both herbaceous and woody species. We 
suggest that similar disturbance appears in the spruce-fir forest, and 
in particular in the grassy balds surrounded by spruce-fir. 

The collecting of herpetofauna in the Park for research purposes is of 
unquestioned value to the scientific understanding and management of 
Park resources, though little collecting ethic is administered by Park 
staff and some studies have caused impacts. Sometimes the value of the 
derived data warrants temporal impacts, and this is a value judgement 
only the Park staff can evaluate. However, we have noticed with 
increasing frequency the presence of collecting activity (e.g., 
overturned rocks, moved logs, broken open tree trunks). The Park staff 
should continue to exercise tight but judicious control in issuing 
permits to collect amphibians and reptiles in the Park, and in approval 
of research programs to be carried out there. Aside from the obvious 
concerns about over-collecting and habitat disturbance, care should be 
taken to guarantee the genetic integrity of populations is maintained. 
Translocation experiments should receive especially thorough review. In 
general, it may be appropriate to request what would amount to a 
biological environmental impact assessment prior to approving collecting 
and/or research in the Park. 



163 



FUTURE RESEARCH 

There is too little information available on geographic variation in 
life history characteristics of wide ranging species. The southern 
Appalachians offer an ideal research area for studies aimed at comparing 
life history strategies of species which range from low elevation to 
high. Many of the species indicated by an asterisk, in Table 1 would be 
suitable for such study (e.g., Bufo americanus , Hyla crucifer , 
Desmognathus quadramaculatus , Eurycea bislineata , Diadophis punctuatus , 
Nerodia sipedon ) . These studies might be coupled with investigations of 
thermal ecology to better understand adaptation of these species to high 
elevation environments. In particular, it would be valuable to know to 
what extent any observed differences between low and high elevation 
populations in critical thermal maximum and critical thermal minimum are 
based on acclimation and how much to genetic differentiation. Thermal 
considerations may be implicated in the evolution of melanism in high 
elevation populations of Thamnophis sirtalis . The extent of melanism, 
both in terms of the proportion of the population exhibiting it and its 
geographic and elevational limits needs documentation. 

Data is lacking on population densities for those species of amphibians 
and reptiles as they occur in spruce-fir forest. Without such data, 
bioraass estimates are impossible and it is not possible to evaluate the 
importance of the species in terms of energy flow. In this regard, 
Table 1 is misleading in according each species equal weight. Whereas 
salamanders like Plethodon jordani and Desmognathus ochrophaeus are very 
abundant at high elevations within their range, certain other species 
(e.g., the spring peeper, Hyla crucifer ) are reported in spruce-fir 
forest, but very infrequently. 

Resource management oriented research should concentrate on the effects 
of acid precipitation and European wild boar rooting as well as on the 
relationships between salamander communities and the spruce-fir forest 
which have not previously been investigated in the Southern 
Appalachians. 



164 



LITERATURE CITED 

Abrahamsen, G. and R. Hornvedt. 1976. Impacts of acid precipitation on 
coniferous forest ecosystems. Proc. Internat. Symp. on Acid 
Precipitation and the Forest Ecosystem (1st), May 12-15, 1975, 
Columbus, Ohio. pp. 991-1009. 

Belden, R.C. and M.R. Pelton. 1975. European wild hog rooting in the 
mountains of East Tennessee. Proc. Southeastern Game and Fish 
Comm. Conf., 29:665-671. 

Brodie, E.D., Jr. and R.R. Howard. 1973. Experimental study of 
Batesian mimicry in salamanders Plethodon jordani and Desmognathus 
ochrophaeus . Amer. Midi. Nat., 90:38-46. 

Hairston, N.C. 1949. The local distribution and ecology of the 
plethodontid salamanders of the southern Appalachians. Ecol. 
Monogr., 19:47-73. 

Highton, R. and T.P. Webster. 1976. Geographic protein variation and 
divergence in populations of the salamander Plethodon cinereus . 
Evolution, 30:33-45. 

Howe, T.D. and S.P. Bratton. 1976. Winter rooting activity of the 
European wild boar in the Great Smoky Mountains National Park. 
Castanea, 41:256-264. 

Howe, T.D., F.J. Singer and B.B. Ackerman. 1981. Forage relationships 
of European wild boar invading northern hardwood forest. J. 
Wildlife Management, 45:748-753. 

Huckabee, J.W., C. Goodyear and R.D. Jones. 1975. Acid rock in the 
Great Smokies: Unanticipated impact on aquatic biota of road 
construction in regions of sufide mineralization. Trans. Amer. 
Fish. Soc, 104:677-684. 

Huff, M.H. 1977. The effect of the European wild boar ( Sus scrofa ) on 
the woody vegetation of Gray Beech forest in the Great Smoky 
Mountains. Research/Resource Management Report No. 15. National 
Park Service, Southeast Region, Uplands Field Research Laboratory. 
98 pp. 

Huheey, J.E. 1966. The desmognathine salamanders of the Great Smoky 
Mountains National Park. J. Ohio Herp. Soc, 5:63-72. 

Knabe , W. and K.H. Gunther. 1976. Investigation on effects of the 
forest canopy on acid and sulfur precipitation in the Ruhr 
District, Germany. Proc. Internat. Symp. on Acid Precipitation and 
the Forest Ecosystem (1st), May 12-15, 1975, Columbus, Ohio. p. 
895. 



165 



Mathews, R.C., Jr. 1984. Distributional Ecology of Stream-Dwelling 
Salamanders in the Great Smoky Mountains National Park. M.S. 
Thesis, Graduate Program in Ecology, University of Tennessee, 
Knoxville . 

Mathews, R.C., Jr. and G.L. Larson. 1980. Monitoring aspects of acid 
precipitation and related effects on stream systems in the Great 
Smoky Mountains National Park. Proc. 1st Conf. Soc. Environ. 
Toxicology Chemistry (SETAC), Nov. 24-25, 1980, Washington, D.C. 18 
pp. 

Mathews, R.C., Jr. and E.L. Morgan. 1982. Toxicity of Anakeesta 
Formation leachates to shovel-nosed salamander, Great Smoky 
Mountains National Park. J. Env. Qual., 11:101-106. 

Mathews, R.C., Jr. and C.A. Phillips. 1982. Survey of fishery losses 
in hatcheries near Great Smoky Mountains National Park and their 
relation to acid precipitation. Internal Report, Uplands Field 
Research Laboratory, Great Smoky Mountains National Park. 

Mathews, R.C., Jr., G. Larson and D. Silsbee. 1979. Atmospheric 
deposition studies in the Great Smoky Mountains National Park. 
Proc. 2nd Conf. on Scientific Research in the National Parks, Nov. 
26-30, 1979, San Francisco, California. 9 pp. 

Mathews, R.C., Jr., J.D. Sinks and E.L. Morgan. 1976. Acid drainage 
toxicity and assessment of sodium hydroxide neutralization in 
streams of the Great Smoky Mountains. Proc. 1st Conf. on 
Scientific Research in the National Parks, Nov. 912, 1976, New 
Orleans, Louisiana. 17 pp. 

Nie, N.H. 1983. SPSS X Users Guide. SPSS Inc. Chicago, Illinois, 
pp. 588-600. 

Orr, L.P. 1968. The relative abundance of mimics and models in a 
supposed mimetic complex of salamanders. J. Elisha Mitchell Sci. 
Soc, 84:303-304. 

Scholtz, F. and S. Reck. 1976. Effects of acids on forest trees as 
measured by titration in vitro, inheritance of buffer capacity in 
Picea abies . Proc. Internat. Symp. on Acid Precipitation and the 
Forest Ecosystem (1st), May 12-15, 1975, Columbus, Ohio. pp. 
971-976. 

Scott, CD. and M.R. Pelton. 1975. Seasonal food habits of the 
European wild boar in the Great Smoky Mountains National Park. 
Proc. Southeastern Game and Fish Comm. Conf., 29:585-592. 

Singer, F.J. and B.B. Ackerman. 1981. Food availability, reproduction, 
and condition of European wild boar in Great Smoky Mountains 



166 



National Park Service, Southeast Regional Office, Uplands Field 
Research Laboratory. 25 pp. 

Singer, F.J., W.T. Swank and E.C.C. Clebsch. 1981. Effects of rooting 
by European wild boar upon nutrient release, vertebrate fauna, and 
soil in northern hardwoods. Internal Report, Uplands Field 
Research Laboratory, Great Smoky Mountains National Park. 30 pp. 

Singer, F.J., W.T. Swank and E.C.C. Clebsch. 1982. Some ecosystem 
responses to European wild boar rooting in a deciduous forest. 
Research/Resource Management Report No. 54. National Park Service, 
Southeast Regional Office, Uplands Field Research Laboratory. 25 
pp. 

Tamm, CO. and E.B. Cowling. 1976. Acid precipitation and forest 
vegetation. Proc. Internat. Symp. on Acid Precipitation and the 
Forest Ecosystem (1st), May 12-15, 1975, Columbus, Ohio. pp. 
845-855. 

Taub, F.B. 1961. The distribution of the red-backed salamander, 
Plethodon c. cinereus, within the soil. Ecology, 42:681-698. 

Tilley, S.G. 1981. A new species of Desmognathus (Amphibia: Caudata: 
Plethodontidae) from the southern Appalachia Mountains. Occ. 
Papers Mus. Zool., Univ. Michigan No. 695. 23 pp. 

Tilley, S.G. and J.R. Harrison. 1969. Notes on the distribution of the 
pygmy salamander, Desmognathus wrighti King. Herpetologica, 
25:178-180. 

Tilley, S.G., R.B. Merritt, B. Wu and R. Highton. 1978. Genetic 
differentiation in salamanders of the Desmognathus ochrophaeus 
complex (Plethodontidae). Evolution, 32:93-115. 



167 



BIRDS OF APPALACHIAN SPRUCE-FIR FORESTS: 
DYNAMICS OF HABITAT- ISLAND COMMUNITIES 

Kerry N. Rabenold 

Abstract . --The birds inhabiting the patchy high-elevation 
forests of Spruce and Fir in the southern Appalachians are both 
distinctively boreal compared to the lowland forests and unique 
in their species composition. These communities contain charac- 
teristically southern Appalachian endemic forms among a reduced 
number of species compared to similar northern forests. These 
characteristics are consistent with an island model for the 
dynamics of these communities but a strict application of the 
analogy with oceanic islands is not tenable. Both sedentary and 
highly migratory northern birds are strikingly few in these 
forests and in their absence short-distance altitudinal migrants 
are numerically dominant. These local populations probably 
compete very effectively with tropical migrants that may be 
better adapted to the more concentrated flush of productivity 
and lower densities of residents characteristic of northern 
Spruce-fir. Explanations for the depauperate status of the 
avifauna that appeal to the history of glaciation in the region 
have limited explanatory power. 

Carolina Juncos in Great Smoky Mountains National Park 
migrate short distances al ti tudinal ly and show patterns of sex- 
specific migratory effort that parallel those shown by latitu- 
dinally migrating juncos. Patterns of segregation on wintering 
grounds between Carolina and Northern Juncos and between the 
sexes of Carolinas are variable, depending on climatic conditions. 
A few male Carolinas are year-round residents in the breeding 
habitat while recapture information shows that others migrate to 
nearly the limits of the winter range. Site tenacity of Carolina 
Juncos is high on several time scales, making more thorough study 
of demography feasible. Differential and partial migration among 
these birds is best explained by competitive effects both for 
winter food and for breeding opportunities. 

Research priorities should focus on the island-like dynamics 
of these bird communities and explore the functional limits of 
their populations, particularly the altitudinal migrants. Man- 
agement problems are urgent; the most remediable is the incursion 
of feral swine. The demise of Fraser's Fir will probably bring 
considerable change to the avifauna, diluting the boreal character 
of this unique ecosystem. 

Additional Keywords : montane bird communities, Spruce-fir, 
island biogeography , species diversity, altitudinal migration, 
Junco hyemalis , Great Smoky Mountains. 



1 



Assistant Professor, Department of Biological Sciences, Purdue University, 
West Lafayette, Indiana 47907. 

168 



INTRODUCTION 

The avian communities of Spruce-fir forests of the southern Appalachian 
Mountains are a unique subset of the family of communities extending into New 
England and southern Canada, united and defined by the dominance of Red Spruce 
( Picea rubens ). These avifaunas of the higest ridges of the unglaciated Appa- 
lachians are definitely boreal in character and strikingly distinct from those 
of lower-elevation deciduous forests. Like the coniferous flora, the avian 
assemblies that inhabit the high altitudes are simpler in taxonomic composi- 
tion than their higher-latitude counterparts. Migrants from the tropics are 
conspicuously few in the breeding season and, instead, altitudinal and short- 
distance migrants dominate. Endemic forms characterize the avifauna as they 
do the flora; the Carolina Junco ( Junco hyemalis carol inensis ) is as emblem- 
atic of the birds as Fraser's Fir ( Abies fraseri ) is of the plants. 

The uniquely southern Appalachian relict Spruce-fir ecosystem ties these 
mountains biologically to the alpine systems of the Rockies and to the boreal 
Canadian biome. It covers a far smaller area than a century ago (Korstian 
1937) and is now further threatened by a concentrated dose of the airborne 
pollutants weakening all eastern forests and by invasions of destructive 
insects and feral swine. This symposium is a timely opportunity to take stock 
of the biological character of the birds of this system, our understanding of 
its history and interdependence with others, and prospects for continued study 
and conservation. 

THE STRUCTURE AND DYNAMICS OF THE AVIFAUNA 

The distribution of Spruce-fir forests on southern Appalachian mountain- 
tops resembles an archipelago; it is therefore tempting to ask whether their 
fauna is island-like. In fact, in one major attribute these bird communities 
do resemble those of oceanic islands: their species richness is depauperate 
compared to the extensive coniferous forests of New England, Quebec and New 
Brunswick (Rabenold 1978). Breeding-season censuses in old-growth Spruce-fir 
of the Great Smoky Mountains compared to northwestern Maine show twice as many 
species in the northern forests (e.g., Table 1). In spite of the lower number 
of species, the southern Spruce-fir can contain higher densities of individual 
birds and greater avian biomass. 

Other species could be added to the list provided in Table 1. Uncommon 
but characteristic species that can be difficult to census include Saw-whet 
Owls ( Aegolius acadicus ) , Ruffed Grouse ( Bonasa umbellus ) and Olive-sided 
Flycatchers ( Nuttallornis borealis ). Species mostly confined to special sub- 
habitats include Black-throated Blue Warblers ( Dendroica caerulescens ) in 
Rhododendron thickets and Chestnut-sided Warblers ( Dendroica pennsyl vanica ) in 
clearings and disturbed areas. The families of birds represented in Appala- 
chian Spruce-fir are identical north and south, and the genera nearly so. 
Northern Spruce-fir holds a larger number of species that are congeneric — 
high northern species diversity results from increased coexistence of many 
species that are yery similar morphologically and ecologically. Conversely, 
bird species in the southern Spruce-fir tend to be the sole representatives of 
families and are more ecologically distinct from each other. 



169 



Table I. List of breeding birds in spruce-fir forests of 2 study sites: Mount Collins, North Carolina (NC) and Shepherd 
Brook Mountain, Maine (ME). Species are arranged by family and singing male densities per 20 ha are shown in 
parentheses. Densities could not be estimated for some species ( ■fvnm Rahpnnlrl 1Q7R^ 



Shepherd Brook Mountain, Maine 



Mount Collins, North Carolina 



Parulidae 

Dendroica virens (Black-throated Green Warbler) (13) 

D fusca (Blackburnian Warbler) (11) 

D. castanea (Bay-breasted Warbler) (19) 

D. coronata (Yellow-rumped Warbler) (08) 

D. magnolia (Magnolia Warbler) (02) 

D. tigrina (Cape May Warbler) ( + +) 

Parula americana (Parula Warbler) (06) 

Seiurus aurocapillus (Ovenbird) (11) 

Paridae 
Parus atricapillus (Black-capped Chickadee) (04) 

P. hudsonicus (Boreal Chickadee) (02) 

Sylviidae 
Regains satrapa (Golden-crowned Kinglet) (15) 

R. calendula (Ruby-crowned Kinglet) (02) 

Fringillidae 

Junco hyemalis (Dark-eyed Junco) (11) 

Carpodacus purpureus (Purple Finch) (04) 

Zonotrichia albivollis (White-throated Sparrow) (02) 

Pinicola enucleator (Pine Grosbeak) (02) 

Hespcriphona vespertina (Evening Grosbeak) (++) 

Spinas pinas (Pine Siskin) ( + +) 

Loxia curvirostra (Red Crossbill) ( + +) 

Turdidae 

Turdus migratorins (American Robin) (++) 

Catharus ustulata (Olive-backed Thrush) (13) 

C. guttata (Hermit Thrush) (++) 

Sittidae 

Sitta canadensis (Red-breasted Nuthatch) (06) 

Vireonidae 

Vireo solitarius (Solitary Vireo) (06) 

Troglodytidae 

Troglodytes troglodytes (Winter Wren) (11) 

Certhiidae 

Certhia familiaris (Brawn Creeper) (08) 

Apodidae 
Choetura pelagica (Chimney Swift) 

Tyrannidae 
Nuttallornis borealis (Olive-sided Flycatcher) ( + + ) 

Empidona.x flaviventris (Yellow-bellied Flycatcher) ( + +) 

Corvidae 

Cyanocitra crista ta (Blue Jay) 
Perisoreus canadensis (Canada Jay) 
Corvus cora.x (Raven) 

Buteonidae 
Buteo jamaicensis (Red-tailed Hawk) 
B. platypterus (Broad-winged Hawk) 

Picidae 
Dendrocopus villosus (Hairy Woodpecker) 

D. pabescens (Downy Woodpecker) 
Picoides arcticus (Arctic Three-toed Woodpecker) 
Sphyrapicus varius (Yellow-bellied Sapsucker) 
Hylatomas pileatus (Pileated Woodpecker) 

Species richness: .S' = 38 
Species diversity: H = 2.79 



Parulidae 

Dendroica virens (Black-throated Green Warbler) (06) 

D. fusca ( Blackburnian Warbler) ( + + ) 

D. pennsylvanica (Chestnut-sided Warbler) ( + +) 



Paridae 
Parus atricapillus (Black-capped Chickadee) 

Sylviidae 

Regulus satrapa (Golden-crowned Kinglet) 

Fringillidae 
Junco hyemalis (Dark-eyed Junco) 
Loxia curvirostra (Red Crossbill) 



(25) 



(25) 



(52) 
(++) 



Turdidae 

Turdus migratorius (American Robin) (04) 

Catharus fuscescens (Veery) (08) 

Sittidae 
Sitta canadensis (Red-breasted Nuthatch) (20) 

Vireonidae 

Vireo solitarius (Solitary Vireo) (25) 

Troglodytidae 

Troglodytes troglodytes (Winter Wren) (34) 

Certhiidae 

Certhia familiaris (Brown Creeper) (13) 

Apodidae 

Choetura pelagica (Chimney Swift) 



Corvidae 

Cyanocitta cristata (Blue Jay) 

Corvus corax (Raven) 
Buteonidae 

Buteo platypterus (Broad-winged Hawk) 

Picidae 
Dendrocopus villosus (Hairy Woodpecker) 



18 

2.15 



+ <1 singing 6 per 20 ha (possibly transient). 



170 



The pattern of diversification of the avifauna at higher latitudes in 
Appalachian Spruce-fir is a gradual one; West Virginia spruce forests support 
intermediate species diversities (Figure 1). 



3.1 



2.9 



> 2.7 

CO 

QC 

UJ 2.5 

> 

Q 

§ 2-3 
CD 

2.1 



/-»- 



SMOKIES 38 40 42 

°N LATITUDE 



44 



MAINE 



Figure 1. --Species diversity of breeding bird communities of Spruce-fir for- 
ests along a latitudinal cline in eastern North America from North 
Carolina to New Brunswick. Only passerines (Order Passeri formes) 
are considered, so that hawks, owls, and woodpeckers are excluded. 
Diversity is expressed using the Shannon-Weaver information theory 
index (Peet 1974): 

H = - I (p i In p.) 

This index weights both number of species and evenness of represen- 
tation. In North Carolina, the mean number of all bird species is 
17, in West Virginia 23, and in Maine the mean number is 35, dou- 
bling in 10° of latitude. All censuses are in nearly pure, mature 
upland stands dominated by Spruce ( Picea ) and Fir ( Abies ) of at 
least 10 ha. Data are from Stewart and Aldrich (1949) , Stewart and 
Webster (1951), Cruickshank and Cadbury (1954), Adams (1959; Mt. 
Mitchell), Nichols (1968), Alsop (1969; Smokies), Erskine (1969a, 
b), Bush et al_. (1973), Metcalf (1977), Rabenold (1978; including 
Smokies), Christie and Dalzell (1980), Kendeigh and Fawver (1981; 
Smokies), Crowell (1983), Ball et al_. (1984), and Berdine et al_. 
(1984). Square data points indicate censuses by the author. 



171 



In addition, the pattern of increased coexistence of congeneric and confamil- 
ial species with increasing latitude is also a general and gradual one 
(Rabenold 1978). Hubbard (1971) points out that many of the Spruce-fir species 
that are absent in the southern Appalachians are sedentary like the Spruce 
Grouse ( Canachites canadensis ), Canada Jay ( Perisoreus canadensis ) and Arctic 
Three-toed Woodpecker ( Picoides arcticus ). However, most conspicuously absent 
in southern Spruce-fir are the many species and large numbers of New-World 
Warblers ( Parulidae ) so characteristic of northern forests (Brewster 1886).. 
Nearly half of the individual passerines in northern Spruce-fir during summer 
are warblers, especially the genus Dendroica (e.g. Table 1 = 45% warblers), 
that migrate long distances latitudinal ly, often from the tropics. 

Very few warblers breed in southern Appalachian Spruce-fir (3% in Table 
1) and the numerical dominants are instead residents or short-distance mi- 
grants like Carolina Juncos, Winter Wrens ( Troglodytes troglodytes ), Black- 
capped chickadees ( Parus atricapillus ) , Golden-crowned Kinglets ( Regulus 
satrapa ) , Red-breasted Nuthatches ( Sitta canadensis ) and Brown Creepers 
( Certhia familiaris ). These species comprise 80% of individual birds in the 
breeding season, and all of them have winter ranges in the foothills of the 
mountains. Most of these populations are likely migrating only short dis- 
tances altitudinally in autumn and spring. Juncos, chickadees, nuthatches and 
creepers, along with occasional Hairy Woodpeckers ( Dendrocopus villosus ), Blue 
Jays ( Cyanocitta cristata ) and Ravens ( Corvus corax ) can all be found in at 
least the lower reaches of Spruce-fir in winter although very few individuals 
of any species winter there. The numerical dominants among southern Appala- 
chian Spruce-fir birds are likely altitudinal migrants that are at least part- 
ly residential in the breeding habitat. 

Birds of the southern Spruce-fir forests are in general species that are 
more characteristic of northern coniferous forest than of lower elevation 
deciduous forest. With the exception of the Veery ( Catharus fuscescens ), all 
the passerines of the southern forests are common in northern Spruce-fir. Of 
the passerines in Table 1, only the warblers and thrushes are very common in 
low-elevation deciduous forests (Stupka 1963, Kendeigh and Fawver 1981). 
Spruce-fir bird communities in the southern Appalachians are, then, island- 
like in their distinctness from the surrounding lowland communities and their 
greater similarity to distant boreal forest communities. 

This summary so far has been somewhat oversimplified in dealing typologi- 
cally with nearly pure Spruce-fir forest mixed only with some Yellow Birch 
( Betula lutea ) and occasional Mountain Ash ( Sorbus americana ) and American 
Beech ( Fagus grandi folia ) . In the altitudinal transition between northern 
hardwoods and spruce-dominated forest, many other bird species occur. For 
instance, the following species, more characteristic of deciduous and mixed 
forests, were observed at Newfound Gap (1538m elevation), Great Smoky Moun- 
tains, in July 1984: Song Sparrow ( Melospiza melodia ) , Indigo Bunting 
( Passerina cyanea ), Catbird ( Dumetella carolinensis ) , Rufous-sided Towhee 
( Pipilo erythrophthalmus ) , Red-eyed Vireo ( Vireo olivaceus ), Canada Warbler 
( Wilsonia canadensis ), Black-and-white Warbler ( Mniotilta varia ) and Ruby- 
throated Hummingbird ( Archil ochus colubris ). Some mixing of Spruce-fir and 
deciduous avifaunas also occurs, at elevations down to 1000m, in Hemlock 
(Tsuga canadensis ) stands in creek valleys, and in successional stands follow- 
ing fire or windthrow at higher elevations. Of course, during vernal and 

172 



autumnal migrations many species of birds uncharacteristic of the breeding 
fauna pass through the high elevations. In late summer, lowland species like 
the Black-and-white Warbler disperse widely and wander into Spruce-fir forests 
(Burleigh 1948; Stupka 1963; R. Wauer, pers. comm.). Less regular "invasions" 
can have greater impact as in years when transients like Red Crossbills ( Loxia 
curvi rostra ) , Evening Grosbeaks ( Hesperiphona vespertina ), and Pine Siskins 
( Spinus pinus ) arrive; the last species can occur in wery large numbers in 
winters when the Spruce seed production is high, as in 1982 in the Great Smoky 
Mountains. Mountaintop "islands" of Spruce-fir forests do not have sharp 
boundaries, nor are they isolated from the larger montane fauna. 

Theory of island biogeography makes predictions about the behavioral 
characteristics of species present on oceanic islands or in habitat islands. 
In general, species with good colonizing ability have proven to be behavioral- 
ly flexible and often inhabit second growth areas on the "mainland" (MacArthur 
and Wilson 1967; MacArthur 1972). Once part of a depauperate island fauna, 
populations of birds often show ecological release: an expansion of feeding 
behavior, habitat use and/or numbers that presumably results from reduced 
competition from ecologically similar species (Diamond 1975; MacArthur 1972). 

Species representing their families in southern Appalachian Spruce-fir 
are generally not the representatives one might expect on a true island. For 
instance, the Black-throated Green Warbler, the Golden-crowned Kinglet, and 
the Black-capped Chickadee are more characteristic of climax old-growth forest 
than their congeners that are sympatric in the north. The Black-throated 
Green Warbler has proven to be a poor colonizer of offshore islands and less 
flexible in its foraging than other warblers (Morse 1971). Of course the 
sheer distance separating southern Spruce- fir islands from each other or from 
the larger Canadian coniferous forest cannot by itself be a significant 
barrier to colonization to birds that return each summer from the tropics. In 
a study comparing foraging behavior of Spruce-fir birds in the Great Smoky 
Mountains with that shown in northwestern Maine, I found that six species of 
arboreal insectivores were more generalized in their foraging in the southern 
forests, as expected. However, the degree of change was not correlated with 
the degree of expected release from exclusively northern species, suggesting 
that a more general condition was affecting the foraging behavior of these 
populations and causing some of the island-like characteristics (Rabenold 
1978). The ecological characteristics of southern Spruce-fir birds do not 
support a strict analogy with oceanic island avifaunas. 

True islands are thought to be depauperate because distance from a main- 
land species pool depresses likelihood of colonization and because small 
physical area supports small populations with greater probability of local 
extinction. A dynamic equilibrium between colonization and extinction is 
expected on islands (MacArthur and Wilson 1967; Diamond 1969; MacArthur 1972), 
yet no such species turnover can be detected in the near-century since 
Brewster's studies in 1886. Contributing to a species-area relationship can 
also be a limited sample of habitat types on small islands or producer popula- 
tions that themselves show little variety. No strong effect of island area 
can be detected in southern Appalachian Spruce-fir avifaunas with current 
information. Smaller areas like the Black Mountains of North Carolina have 
supported the same avifauna as areas twice as large like the Great Smoky 
Mountains. However, more careful censusing must be done, especially in the 



173 



smaller areas outside the Great Smoky Mountains, before a firm conclusion can 
be drawn concerning the species-area relationship. 

The pattern of increasing bird species diversity and increasing similari- 
ty of coexisting species with increasing latitude that has been shown for 
Appalachian Spruce-fir also applies to eastern deciduous forests (Rabenold 
1979). This generality has led me to look for an explanation of species 
diversity in Spruce-fir that is not tied to its similarity to an archipelago, 
since eastern deciduous forest does not share this characteristic. Even on 
the highest ridges of the southern Appalachians, the climate is more equable 
than that of far northern Spruce-fir. The productive season is less compressed 
into a short summer in the south than in the north and winters are not so 
harsh. Long-distance migrants, especially the warblers, vireos and thrushes, 
undoubtedly can capitalize so effectively on the short burst of summer produc- 
tivity in boreal forests partly because resident temperate species cannot 
effectively track the strong resource oscillations. Food levels in the breed- 
ing season in northern Spruce-fir could be high enough to ease competition and 
promote coexistence between similar species. Densities of food for insecti- 
vores did reach much higher levels in Maine than in the Great Smoky Mountains 
in my 1978 study. Relative food abundance in the north can be due not only to 
an intense burst of productivity in summer, but also to the fact that in winter 
all bird populations must either migrate long distances or endure a boreal 
winter and therefore suffer greater overwinter mortality. In the southern 
Spruce-fir forests, winters are milder but, more importantly, downslope refugia 
exist to which essentially resident populations can easily retreat. The wide- 
spread altitudinal migrations performed by the numerically dominant species 
may be effective enough that overwinter mortality is reduced and arrival time 
hastened, crowding out the later-arriving long-distance migrants. 

In summary, the bird communities of southern Appalachian Spruce-fir for- 
est, and of the peaks of the Great Smoky Mountains in particular, do in many 
respects resemble islands of Canadian biome. In spite of their distinctiveness 
from downslope communities, the boreal distribution of most of the species and 
their low species diversity, they do not seem to function strictly as true 
islands. Most importantly, they are dominated by al titudinally migrating 
populations so that the dynamics of their populations are likely very different 
from those of northern Spruce-fir, where latitudinally migrating warblers 
dominate. The next section will present further evidence of the distinctive- 
ness of this avifauna and possible application of the island paradigm over 
evolutionary time. 

HISTORICAL DISTINCTNESS OF THE MONTANE ISLAND RELICTS 

Endemism is an indicator of the degree of isolation of a fauna over evo- 
lutionary time and of the independence of development from other systems. 
Levels of endemism have been used to recreate the history of speciation in 
studies of other montane systems where unique evolutionary pathways are ex- 
pected because of the patchy distribution of high-elevation habitat types (B. 
Vuilleumier 1971; F. Vuilleumier 1981). Seven species of birds characteristic 
of Spruce-fir forests have developed recognized subspecies that are unique to 
the southern Appalachians (south of Pennsylvania) (Table 2). This level of 
taxonomic divergence, although it has not reached recognized speciation, 
establishes that the southern Appalachian Spruce-fir avifauna is distinctive 



174 



Table 2. --Avian species breeding in Spruce-fir forests that show recognized 
subspecies endemic to the southern Appalachians. (AOU checklist, 
5th ed.) 

Species Endemic form Common Name 

Junco hyemalis _J.hk carol inens is Carolina Dark-eyed Junco 

Parus atricapillus j\a_. practicus Appalachian Black-capped 

Chickadee 

Troglodytes troglodytes T.t^. pullus Southern Winter Wren 

Certhia fami 1 iaris C_._f. nigrescens Southern Brown Creeper 

Vireo solitarius V^.s^. al ticola Mountain Solitary Vireo 

Dendroica caerulescens d_.c. cairnsi Cairns's Black-throated 

Blue Warbler 

Sphyrapicus varius S_.v^. appalachiensis Appalachian Yellow-bellied 

sapsucker 

more than just for its paucity of species; this relict fauna has diverged 
evol utionarily from the northern fauna to form a unique assembly. 

The island model of community dynamics is probably more applicable to 
this montane system on an evolutionary time scale than in ecological time. 
The southern Appalachians served as the colonizing source for emerging north- 
ern Spruce-fir habitats following the last glaciation in North America. As 
the retreating glaciers allowed expansion of northern Spruce-fir, coniferous 
forests in the Southeast began to shrink toward the mountains (Watts 1970; 
Hubbard 1971; Delcourt and Delcourt, this volume). Groups like the warblers 
( Parulidae ) that had adapted to boreal forest and speciated during successive 
glaciations moved northward (Mengel 1964; Cook 1969). Selective pressures 
must have been wery different in the shrinking forests of the southern Appala- 
chians than in the north. The flexibility of colonists was likely at a 
premium in the north, while persistence in small populations through competi- 
tive superiority would have been favored in the south. Species that have 
proven to be good colonizers and flexible in foraging and habitat use, like 
Yellow-rumped Warblers ( Dendroica coronata ) , have since lost their southern 
Appalachian breeding ranges. In contrast, species that are now numerical and 
social dominants in their genera in the north persisted in the southern 
Appalachians (e.g. Black-throated Green Warblers, Golden-crowned Kinglets, 
Black-capped Chickadees). 

Post-glacial southern Appalachian Spruce-fir forest can be likened to a 
shrinking land-bridge island gradually cut off from the mainland by rising 
seas (of deciduous forest). The avifauna of this system seems to fit the 
"persistent relict" pattern (MacArthur et al_. 1972; Wilcox 1978). In partic- 
ular, the Black-throated Green Warbler has been characterized as a competitive 
and social dominant in Maine, and is a poorer colonizer of offshore islands 



175 



than exclusively northern species like the Yellow-rumped Warbler (Morse 1971). 
The Black-throated Green consistently dominates in mature forests in the 
north, while exclusively northern warblers tend more to occur in second- 
growth and edge habitats. The Black-capped Chickadee and Golden-crowned 
Kinglet, representatives of their families in the south, are numerical domi- 
nants in mature northern forests. The exclusively northern Boreal Chickadee 
( Parus Hudsonicus ) and Ruby-crowned Kinglet ( Regulus calendula ) occur more 
commonly in edaphic subclimax communities like bogs and poor upland sites 
(Dixon 1961; Bent 1964; Erskine 1971). In addition, species occurring in both 
the north and southern Appalachians in these families are more specialized in 
their foraging than their exclusively northern congeners (Rabenold 1978). The 
southern Spruce-fir avifauna appears to be a nonrandom subset of the larger 
northern fauna in that selection for persistence in an island-like depauperate 
fauna has probably favored competitively dominant species. The northern avi- 
fauna, by comparison, consists more of wery similar, generalized species. 
This "stacking" of generalists in the north is probably allowed by seasonally 
compressed productivity and winter limitation of consumers, as outlined 
earlier. The historical selection for dominant specialists in the south is 
probably currently reinforced by poorer resource conditions during the breeding 
season and the greater success of locally resident, altitudinally migrating 
species. 

Alternative historical perspectives paint a different picture of the 
origins of the characteristically depauperate southern Spruce-fir avifauna. 
Kendeigh and Fawver (1981) suggest that the avifauna of the Great Smoky Moun- 
tains Spruce- fir is depauperate because of insufficient time (2000-4000 yr) 
for recolonization of these forests by species driven north by the mid-Holocene 
post-glacial xerothermic period (the hypsithermal interval of Deevey and Flint 
1957; see also Hubbard 1971). During this warmer and drier epoch, southern 
Appalachian Spruce-fir was likely of much lesser extent than in the recent 
century (Whittaker 1956; Delcourt and Delcourt, this volume). This shrinkage 
would certainly have exacerbated island effects, but evidence that it actually 
caused local extinction is lacking. Of course, such reconstructions of bio- 
geographic processes over evolutionary time are very difficult to test, and 
they are not logically incompatible with the kind of ecological explanation I 
proposed earlier. That 3000 yr is insufficient time for recolonization of the 
southeastern Spruce- fir by tropical migrants passing through each spring may 
seem implausible in view of the rapid range expansions of eastern bird species 
in the 20th century. Furthermore, several species that are characteristic of 
Spruce-fir in New England occur at the lower elevations in the Great Smoky 
Mountains but generally not in the high-elevation Spruce-fir. Ovenbirds 
( Seiurus aurocapillus ) , Parula Warblers ( Parula americana ) and Blackburnian 
Warblers ( Dendroica fusca ) are common in northern Spruce-fir but in the 
Smokies are restricted to breeding at lower elevations. This suggests at 
least that some ecological factors limit the presence of these long-distance 
migrants in the southern Spruce-fir. In addition, many birds characteristic 
of Spruce-fir in New England are common winter residents in the Smokies: for 
example, Yellow-rumped Warblers, Ruby-crowned Kinglets, White-throated Sparrows 
( Zonotrichia albicollis) and Purple Finches ( Carpodacus purpureus ). The chal- 
lenge in this field is to devise tests of these alternative explanatory 
schemes, and the Spruce-fir avifauna, because of the clear patterns it pre- 
sents, should continue to be a fruitful subject. 



176 



FUNCTIONAL BOUNDS OF SPRUCE-FIR POPULATIONS: 
ALTITUDINAL MIGRATION OF CAROLINA JUNCOS 

Al titudinal migration is probably a key to the structure of southern 
Appalachian Spruce-fir avian communities. The ability of the numerically 
dominant populations to escape the boreal winter of the high elevations just 
by moving a few kilometers downs! ope may help explain the relative absence of 
latitudinal migrants. This seasonal movement among habitat types also demon- 
strates the importance of ecological conditions in other ecosystems for popu- 
lation dynamics and community structure in Spruce-fir. 

Since 1979, Patricia Parker Rabenold and I have studied the altitudinal 
migration of the most abundant breeding bird species in the Spruce-fir system 
of the Great Smoky Mountains: the Carolina Junco (Rabenold and Rabenold, in 
press). Our basic empirical questions have been: (1) Over what distance does 
this migration occur? (2) Is there differential migration between the sexes 
similar to that found for latitudinal ly migrating juncos (Ketterson and Nolan 
1976)? (3) How commonly does year-round residency in the breeding habitat 
occur? (4) Does the winter range of the latitudinally migrating northern 
Dark-eyed Junco (J_._h. hyemal is ) overlap that of the Carolina Junco? and (5) 
How likely are juncos to remain at the same site within winters and between 
years? Our conceptual goal has been to ask whether the workings of this short- 
distance migration system can be understood using ideas developed in studies 
of latitudinal migrants concerning the ecological determinants of variation in 
migratory effort. 

Carolina juncos cover a range of climates and habitats during their annual 
cycle that is comparable to that encountered by the northern subspecies in more 
than a thousand kilometers of latitudinal travel. Over 4 years we have cap- 
tured and individually marked 1832 juncos of both subspecies in the drainage 
of the Oconaluftee River from Indian Gap, in Spruce-fir breeding habitat within 
Great Smoky Mountains National Park, to Whittier, NC, 21 km distant. Over this 
1000m elevational gradient, mean January temperatures differ by more than 7°C 
and snow cover is much more common in winter at the high elevations. We have 
studied juncos at 22 different sites in this valley but for this discussion I 
will refer simply to distant sites near Whittier (610m altitude, 21 km from 
Indian Gap), low elevation sites near Oconaluftee Ranger Station (640m, 16 km), 
middle elevation sites near Smokemont (730m, 13 km) and high-elevation sites 
in the vicinity of Indian Gap (1610m) in breeding habitat. Juncos do not 
generally breed below 1200m elevation in this drainage, except in hemlock 
stands along streams. 

In the Oconaluftee drainage, most juncos spend the winter outside the 
breeding habitat (below 1200m). Using mark-recapture calculations, we esti- 
mate that more than 150 individuals use a feeding site at Smokemont or 
Oconaluftee, but fewer than 20 use sites at Indian Gap. Because the breeding 
habitat is a very small area compared to the winter range, this indicates that 
only a small proportion of the population spends the winter on the Spruce-fir 
breeding ground. Most Carolina Juncos in the Oconaluftee drainage winter more 
than 10 km from breeding habitat at elevations from 600-800m in deciduous 
forests and clearings. Great Smoky Mountains National Park is large enough to 
encompass most, but not all of the winter population of Carolina Juncos. 



177 



Winter flocks of juncos within Park boundaries in the study drainage are 
composed mostly of Carolina Juncos, and most of these Carol inas are males 
(Figure 2). Of 1654 individuals captured in January, February and March 1980- 
1984 in the Oconaluftee valley 76% were Carol inas and 77% of the Carolinas 
were male (mostly near Oconaluftee and Smokemont). Outside Park boundaries, 



WINTER COMPOSITION OF JUNCO POPULATIONS 

Subspecies : Caroline | 
Carolina Sex : Male X////A 



Park 
Boundary 



t2000 




15 10 5 

DISTANCE FROM RIDGE CREST (Km) 

Figure 2. --Composition by subspecies and sex of winter flocks of Dark-eyed 
Juncos (Carolinas - ^_.\\_. carol inens is , and Northerns - J^. 
hy emalis ) in the Oconaluftee drainage 1980-1984. Sample sizes are: 
Whittier - 101 individuals of both subspecies; Oconaluftee - 495; 
Smokemont - 339; Indian Gap - 108. Subspecies and sex determina- 
tions are made by size and plumage characteristics. Data are from 
January/February 1981, 1982 and 1984 and from March 1980. Results 
from March 1981 and 1982 are omitted because spring migration was 
underway (1981) or complete (1982). 



farther than 20 km from breeding habitat, 83% have been Northerns in January 
(N = 97) and 80% of the Carolinas have been female (N = 20) (Figure 2). In 
the breeding habitat of Spruce-fir around Indian Gap, few wintering juncos are 
Northerns (25%; N = 108) and wery few Carolinas are females (15%; N = 66). The 
subspecies of juncos segregate in winter: Carolinas remain at the feet of 
mountains bearing Spruce-fir while Northerns winter mostly farther from the 
peaks and throughout the Piedmont. Differential migration between the sexes of 



178 



Carolina Juncos is striking since males more commonly remain close to breed- 
ing habitat than females. Partial migration among male Carol inas results in 
some year-round residency in the breeding habitat. Recapture information from 
marked birds shows that some males remain on the same small home range year- 
round for several years in Spruce-fir forest, while other males migrate from 
the crest of the Smokies to winter up to 20 km away in lowland deciduous 
forest. 

Patterns of subspecies segregation in winter, and of differential migra- 
tion of the sexes in Carolina Juncos, are variable from year to year. The 
winter of 1980-1981 was colder than that of 1981-1982. For 7 weather stations 
within 30 km of Oconaluftee, temperatures were 2.7°C colder in January and 
4.2°C colder in February of 1981 compared to 1982, and these months were 4-7°C 
colder than average in 1981. In January 1981, 87% (N = 203) of juncos were 
Carolinas in the Oconaluftee drainage, compared to 66% (N = 319) in 1982 
(p< .001; x" test). Females were better represented in the study area in the 
warm January of 1982 (37%) than the colder January of 1981 (17%) (p < .001; 
X 2 ). Because Carolinas are larger than Northerns and males are larger than 
females, the pattern of Carolina males dominating at middle and high altitudes 
means that average body size of wintering juncos is higher at higher altitudes. 
Even within the class of Carolina males, the cold winter of 1981 produced a 
gradient of body size in the Oconaluftee drainage that did not appear in 1982. 
In general, smaller juncos (Northerns, Carolina females and small Carolina 
males) were better represented at middle and high elevations during a milder 
winter. Timing of spring migration is also variable. In the warm winter of 
1982, juncos had left the winter grounds near Smokemont and Oconaluftee by the 
first week in March. In the two previous colder years, juncos had either just 
begun migratory movement (1981) or were still in a stable winter distribution 
(1980) at the same calendar dates. The altitudinal migrations of Carolina 
Juncos are flexible and apparently responsive to changing environmental condi- 
tions . 

In spite of some variation in timing, the Carolina Junco population 
usually recolonizes Spruce-fir by late March each spring. Males arrive before 
females, but not much before. In March 1981, the first-arriving migrants at 
Indian Gap were 91% male (N = 35), but in March 1982, when the low-elevation 
winter grounds had been vacated, the sex ratio was near 1:1 (54% male; N = 39). 
This arrival by females in the first week of March is fully 6 weeks before the 
earliest recorded egg-laying of Carolina Juncos and 2-6 weeks before the 
earliest recorded arrivals of long-distance migrants like Black-throated Green 
Warblers, Solitary Vireos, Blackburnian Warblers, and Veerys (Stupka 1963). 
Exclusively northern warblers like the Baybreasted ( Dendroica castanea ) and 
Cape May (D. tigrina ) do not pass through the park until mid to late April, 
when Juncos are already nesting. Altutudinal migrants like Carolina Juncos 
clearly get a head-start on territory formation and breeding over the late- 
arriving tropical migrants. 

We have used recapture data to analyze site tenacity in Dark-eyed Juncos 
over several time scales: (1) Carolina Juncos show greater probabilities of 
recapture than Northerns both between and within winter months, but no greater 
tendency to visit capture sites separated by 200-400 m, probably indicating 
higher survival by Carolinas; (2) male and female Carolinas show no difference 
in probability of recapture in winter but females seem to have larger ranges; 



179 



(3) Carolina Juncos are more site-tenacious in winter at high altitudes than 
low; (4) Carol inas return faithfully both to winter and summer ranges after 
migratory absences. To illustrate the last result, 79% of birds captured in 
successive winters had returned to the site where originally banded (N = 66) 
and 97% (N = 29) of marked birds censused in successive summers were found on 
the same breeding territories as the previous year. All of the 21 birds 
banded in winter in Spruce-fir that have been recaptured in a later winter 
were found at the same sites as before. Furthermore, we have banded 164 
Carol inas in breeding habitat in January or March and resighted 57 of these 
in the following breeding season. All resightings have been within 200m of 
the original capture. Within their system of altitudinal migration, Carolina 
Juncos are surprisingly sedentary--they tend not to stray from relatively small 
ranges except for the brief bouts of migratory movement in spring and fall and 
they tend to return to sites after a migratory absence. Further study is 
needed of winter ranges and natal dispersal before an accurate picture' of the 
demography of this population will be possible, and these patterns of site 
tenacity make such study feasible. 

Three hypotheses developed in the study of long-distance migrants to 
explain differential and partial migration lend some insight into this system 
of altitudinal migration. Migratory effort and choice of wintering ground by 
Carolina Juncos appears to be a flexible response adjustable to pressures 
created by behavioral interactions with other birds. In reviewing evidence 
for adaptive adjustment of migratory effort in latitudinal migrants, especially 
Northern Juncos, Ketterson and Nolan (1983) point out that (1) physiological 
tolerances that vary systematically between classes of individuals could 
produce differential migration and winter segregation, (2) behavioral differ- 
ences among individuals in dominance interactions and competition for food in 
winter could produce similar patterns, and (3) competition in the breeding 
season for territories and mates could contribute to the advantage of residency 
in, or wintering near, the breeding habitat. Patterns of survival and ranging 
revealed by mark-recapture calculations are consistent with the hypothesis that 
small competitively subordinate classes of juncos - Northerns and female 
Carol inas - either suffer greater mortality or are forced to range more widely 
in search of food in winter. 

The basic patterns of assortment on the winter grounds in this study are 
consistent with all 3 hypotheses considered. Carolina males have been social- 
ly dominant over females and Northerns in our preliminary aviary experiments. 
This dominance can produce a marked effect on diet when a range of food types 
is available - subordinates in flocks shift their diets considerably away from 
foods preferred in isolation (see also Fretwell 1969; Balph 1977; Baker et al . 
1981 on dominance in Northern Juncos). Female Carol inas might be forced to 
migrate farther to avoid competition with males and to range more widely on 
the winter grounds as well. The warm winter of 1982 may have ameliorated such 
competitive effects and allowed females and Northerns to winter in greater 
numbers in the study area. The larger body size of Carolina males compared to 
females and Northerns should also confer greater physiological tolerance of 
cold and fasting at high altitudes. In addition, territory establishment in 
spring by males may exert selective pressure on them to remain as near as 
possible to places where they are likely to breed to reap the benefits, 
described in other studies, of dominance determined by prior occupancy. While 
consistent with the major pattern of male-biased sex ratio at high altitudes 
in winter, these last two considerations are of limited application to 
Carol ina Juncos . 

180 



The balance of selective forces determining migratory effort in Carolina 
Juncos are likely different from those affecting long-distance migrants. 
Physiological and distributional studies suggest that size-related tolerance 
of cold and fasting may not be a plausible explanation of differential migra- 
tion even in Northern Juncos (reviewed in Ketterson and Nolan 1983). The short 
distances separating male and female Carol inas in winter make it likely that 
energetic costs of migratory travel and effects of wintering ground on time of 
return to Spruce-fir will be relatively less important, and competitive effects 
more important, than for long-distance migrants. Year-round residency by males 
in Spruce-fir is best explained by the "home court" advantage - a head-start 
on breeding on an already-established territory. Differential migration of 
the sexes of Carolinas is best explained by competitive effects in winter, but 
more study is needed of the relationships among competitive interactions, 
movement patterns, survival and reproductive success. The altitudinal migra- 
tions of Carolina Juncos could prove to be a model for similar movement 
patterns of other numerically dominant species of the Spruce-fir breeding bird 
community. 

FUTURE AVIAN RESEARCH AND CONSERVATION PRIORITIES 

Our understanding of the determinants of community structure in the 
southern Appalachian Spruce-fir avifauna is imperfect and this unique, pecu- 
liarly southern Appalachian assembly continues to be enigmatic. In the next 
decade this small and probably fragile ecosystem will undoubtedly be changed 
by the environmental stresses now besetting it. Some of these issues can only 
be addressed at the national level but some are local management matters. The 
future of this relict ecosystem depends mainly on the degree to which it func- 
tions as a biological island, and much research will be needed to properly 
address that question. To the extent that Spruce-fir-clad mountaintops are 
islands, the expanse of this habitat in Great Smoky Mountains National Park may 
have already proven too small to support a complete boreal avifauna and the 
limits of the Park too narrow to fully protect even the remaining populations. 
Further inroads into this habitat and destruction of winter habitat within and 
outside the Park can only lead to further dilution or diminution of a fauna 
that is the most unique and vulnerable ward of the Park. Little of it is 
adequately protected elsewhere, and none in such a pristine state. 

The application of the theory of island biogeography to conservation 
issues and the management of wildlife preserves has been hotly debated recent- 
ly (May 1975, Terborgh 1976; Soule and Wilcox 1980; Simberloff and Abele 1982). 
Some clear empirical lessons remain, however. Oceanic islands and habitat 
islands do have fewer species than large expanses of similar habitats - the 
existence of a positive relationship between area of habitat and number of 
species has long been clear. Furthermore, there are repeated patterns in 
depauperate faunas regarding which species are absent relative to the regional 
species pool. Southern Appalachian Spruce-fir supports a low diversity of 
bird species. Comparison with lower-elevation habitats is confused by the 
general trend for diversity to decline with altitude (Able and Noon 1976). 
More importantly, southern Spruce- fir is lacking the abundance of neotropical 
migrants common to northern Spruce-fir, and parallels can be found in studies 
of deciduous forest fragments. In a comprehensive study of remnant woodlots 
in the eastern U.S., Whitcomb and coworkers (1981) point out that neotropical 
migrant bird species, especially the warblers that are forest interior 



181 



specialists, are the most vulnerable to extirpation as woodlands are fragment- 
ed into smaller and more isolated patches. These authors attempt to explain 
the sensitivity of long-distance migrants to habitat fragmentation by the 
"unsuitability of several life history features common to forest interior 
neotropical migrants" (p. 190). The applicability of the parallel with south- 
ern Spruce- fir habitat islands can be judged only once better information 
concerning composition of Spruce-fir bird communities of the southern Appala- 
chians is in hand. 

Further study is needed of the composition of bird communities in Spruce- 
fir forests, particularly of the variability between sites within a large 
range like the Great Smoky Mountains, and differences in smaller ranges like 
the Plott Balsams and Black Mountains of North Carolina. If the island 
paradigm is applicable, there should be an appreciable species-area effect 
within the southern Appalachians. The absence of chickadees on Mt. Mitchell 
(Burleigh 1948; Adams 1959) suggests that such a pattern may exist. As a 
calibration for these comparisons, more must also be known about the year-to- 
year variation within a particular site. 

To intelligently anticipate the fate of the southern Spruce-fir system, 
further study should be made of the effects of downslope systems on high- 
altitude population dynamics. Dispersal data would help reveal the degree to 
which Spruce-fir populations are replenished by the productivity of lower- 
elevation populations. It is also possible that the composition of downslope 
communities is altered by proximity to Spruce-fir. The possibly reciprocal 
effects at the ecotone of Spruce-fir could be explored with altitudinal 
transects of censusing and banding from Hemlock or northern hardwoods into 
Spruce-fir. Possibly most important is further study of altitudinal migration. 
The structure of Spruce-fir bird communities may be vulnerable to changes in 
the low-elevation wintering grounds of short-distance migrants. For instance, 
if cleared areas at low elevations within the Park are allowed to revert to 
forest, Carolina Junco populations could be forced outside the Park boundaries 
where they could suffer from effects of shrinking habitat. Before this effect 
could be reasonably predicted, however, surveys of habitat preferences of 
wintering altitudinal migrants would have to be undertaken. Our study of 
Carolina Juncos suggests that one sex is particularly affected by conditions 
outside the Park; studies of other altitudinal migrants could similarly explore 
the functional limits of Spruce-fir populations. More extensive censuses in 
both winter and summer would also document effects that changes in the densi- 
ties of altitudinal migrants might have on the representation of long-distance 
migrants in the community, thereby testing some of the ecological hypotheses 
presented here for the determination of community structure. 

The last half of this decade will bring tests of the stability and in- 
vasibility of the Spruce-fir avifauna, but as experiments these tests may con- 
fuse the causes of change. The wholesale death of Fraser's Fir, whether the 
causes are airborne pollutants or destructive insects, can probably no longer 
be prevented. The opening of the canopy has already begun to change the forest 
floor by encouraging growth of Rubus thickets. Productivity will become more 
concentrated near the ground, adversely affecting canopy- foraging and canopy- 
nesting birds like the warblers and kinglets. The climate and cover near the 
ground will also change, perhaps interfering with near-ground foragers and 
nesters like the juncos and wrens. These trends will be exacerbated by 



182 



increased wind-throw of spruce following the death of fir. As broad-leafed 
vegetation invades, deciduous-forest bird species will probably expand their 
altitudinal ranges and diminish the boreal character of the avifauna. Cat- 
birds, Towhees , Song Sparrows and others can be expected. Confusing these 
effects will be the increasingly destructive effects of feral swine. These 
animals have already turned over large areas of forest floor and are bound to 
have a detrimental effect on ground-nesting species. This situation is 
probably controllable, and the threat to the ecosystem is serious. If the 
mission of a National Park is partly to preserve working ecosystems, the 
Spruce- fir of the Great Smoky Mountains is probably the most unique the Park 
shelters and the one most threatened, in part because of its small size. 
Research and conservation energies should be focused there, and the avifauna 
holds great potential rewards for both. 

ACKNOWLEDGMENT 



un- 



I am greatly indebted to the administration and staff of Great Smoky Mo 
tains National Park for their cooperation and help over the last 12 years, 
especially Duane AT ire, Stu Coleman, Don DeFoe, Charles Harris, Janet Pierson 
and Roland Wauer. 

LITERATURE CITED 

Able, K. P., and Noon, B. R. 1976. Avian community structure along elevation- 
al gradients in the northeastern United States. Oecologia 26: 275-294. 

Adams, D. A. 1959. Breeding bird census 9: Fraser's fir forest. Audubon 
Field Notes 13: 464. 

Alsop, F. J. Ill 1969. Breeding bird census 21: Virgin Spruce-fir forest. 
Audubon Field Notes 23: 716. 

Baker, M. C, Belcher, C. S., Deutsch, L. C, Sherman, G. L., and Thompson, D. 
B. 1981. Foraging success in junco flocks and the effects of social 
hierarchy. Anim. Behav. 29(1): 137-142. 

Ball, H. et al_. 1984. Breeding bird census 75: Virgin spruce-northern hard- 
woods forest. Amer. Birds 38: 90. 

Balph, M. H. 1977. Winter social behaviour of dark-eyed juncos: communica- 
tion, social organization, and ecological implications. Anim. Behav. 25(4): 
859-884. 

Bent, A. C. 1964. Life histories of North American birds. Dover, New York, 
New York, USA. 

Berdine, M. et al_. 1984. Breeding bird census 74: Birch-spruce-fir forest. 
Amer. Birds 38: 89. 

Brewster, W. 1886. An ornithological reconnaissance in western North 
Carolina. Auk 3: 94-112, 173-179. 



183 



Burleigh, T. D. 1948. Bird life on Mt. Mitchell. Auk 58: 334-345. 

Bush, K. E., Hutton, E. E., Jr., Rudy, C, and Rudy, M. 1973. Breeding bird 
census 50: Fir-spruce swamp. Amer. Birds 27: 981. 

Christie, D. S., and Dalzell, B. 1980. Breeding bird census 61: Red spruce 
forest. Amer. Birds 34: 60. 

Cook, R. E. 1969. Variation in species density in North American birds. 
Syst. Zool . 18: 63-84. 

Crowell, K. 1983. Breeding bird census 62: Young spruce forest. Amer. Birds 
37: 70 

Cruickshank, A. D., and Cadbury, J. M. 1954. Breeding bird census 35: Climax 
red and white spruce forest. Audubon Field Notes 8: 381. 

Deevy, E. S., and Flint, R. F. 1957. Postglacial hypsithermal period. 
Science 125: 182-184. 

Diamond, J. M. 1969. Avifaunal equilibria and species turnover rates on the 
Channel Islands of California. Proc. Nat. Acad. Sci . USA 64: 57-63. 

Diamond, J. M. 1975. Distributional ecology of New Guinea birds. U\_ M. L. 
Cody and J. M. Diamond (eds.) Ecology and Evolution of Communities, p. 342- 
444. Harvard Univ. Press, Cambridge, Mass., USA. 

Dixon, K. L. 1961. Habitat distribution and niche relationships in North 
American species of Parus . Ir± F. W. Blair (ed.) Vertebrate Speciation, 
p. 179-216. Univ. Texas Press, Austin, Texas, USA. 

Erskine, A. J. 1969a. Breeding bird census 20: Fir-spruce forest. Audubon 
Field Notes 23: 714-716. 

Erskine, A. J. 1969b. Breeding bird census 25: Upland coniferous forest. 
Audubon Field Notes 23: 718-719. 

Erskine, A. J. 1971. A preliminary catalogue of bird census plots in Canada. 
Canadian Wildlife Service Progress Notes No. 30. 

Fretwell, S. D. 1969. Dominance behavior and winter habitat distribution in 
juncos ( Junco hyemalis ) . Bird Banding 40: 1-25. 

Hubbard, J. P. 1971. The avifauna of the southern Appalachians: Past and 
present. In_ P. C. Holt (ed.) The Distributional History of the Biota of the 
Southern Appalachians, p. 197-232. Virginia Polytech. Inst, and State Univ., 
Research Div. Monogr. 4, Blacksburg, Virginia, USA. 

Kendeigh, S. C, and Fawver, B. J. 1981. Breeding bird populations in the 
Great Smoky Mountains, Tennessee and North Carolina. Wils. Bull. 93(2): 
218-242. 



184 



Ketterson, E. D., and Nolan, V., Jr. 1976. Geographic variation and its 
climatic correlates in the sex ratio of eastern-wintering Dark-eyed Juncos 
( Junco hyemal is ) . Ecology 57: 679-693. 

Ketterson, E. D. , and Nolan, V., Jr. 1983. The evolution of differential 
bird migration. Current Ornithology 1: 357-402. 

Korstian, C. F. 1937. Perpetuation of spruce on cut-over and burned lands in 
the higher southern Appalachian Mountains. Ecol . Monogr. 7: 125-167. 

MacArthur, R. H. 1972. Geographical Ecology. Harper and Row, New York, New 
York, USA. 

MacArthur, R. H., and Wilson, E. 0. 1967. The theory of island biogeography . 
Princeton Univ. Press, Princeton, New Jersey, USA. 

MacArthur, R. H., Diamond, J. M. , and Karr, J. R. 1972. Density compensation 
in island faunas. Ecology 53: 330-342. 

May, R. M. 1975. Island biogeography and the design of wildlife preserves. 
Nature 254: 177-178. 

Mengel , R. M. 1964. The probable history of species formation in some north- 
ern wood warblers (Parulidae). The Living Bird 3: 9-44. 

Metcalf, L. N. 1977. Breeding bird census 66: Coniferous forest. Amer. 
Birds 31: 53-54. 

Morse, D. H. 1971. The foraging of warblers isolated on small islands. 
Ecology 52: 216-228. 

Nichols, W. D. 1968. Breeding bird census 19: Mountain coniferous forest. 
Audubon Field Notes 22: 668-670. 

Peet, R. K. 1974. The measurement of species diversity. Ann. Rev. Ecol. 
Syst. 5: 285-307. 

Rabenold, K. N. 1978. Foraging strategies, diversity, and seasonality in bird 
communities of Appalachian Spruce-fir forests. Ecological Monographs 48(4): 
397-424. 

Rabenold, K. N. 1979. A reversed latitudinal diversity gradient in avian 
communities of eastern deciduous forests. Amer. Natur. 114: 275-286. 

Rabenold, K. N., and Rabenold, P. P. (in press) Variation in altitudinal 
migration and site tenacity among Appalachian Juncos. Auk 

Simberloff, D., and Abele, L. G. 1982. Refuge design and island biogeographi c 
theory: effects of fragmentation. Amer. Natur. 120: 41-50. 

Soule, M. E. , and Wilcox, B. A. Conservation Biology - An Evolutionary- 
Ecological Perspective. Sinauer Assoc, Sunderland, MA, USA. 



185 



Stewart, R. E., and Aldrich, J. W. 1949. Breeding bird populations in the 
Spruce region of the central Appalachians. Ecology 30: 75-82. 

Stewart, R. E., and Webster, C. G. 1951. Breeding bird census 5: Young 
Spruce-fir forest. Audubon Field Notes 5: 316-317. 

Stupka, A. 1963. Notes on the birds of Great Smoky Mountains National Park. 
Univ. of Tennessee Press, Knoxville, Tennessee, USA. 

Terborgh, J. 1976. Island biogeography and conservation: strategy and limi- 
tations. Science 193: 1029-1030. 

Vuilleumier, B. S. 1971. Pleistocene changes in the. fauna and flora of South 
America. Science 173: 771-780. 

Vuilleumier, F. 1981. The origin of high Andean birds. Natural History 90: 
50-57. 

Watts, W. A. 1970. The full-glacial vegetation of northwestern Georgia. 
Ecology 51: 17-33. 

Whitcomb, R. F. , Robbins, C. S., Lynch, J. F. , Whitcomb, B. L., Klimkiewicz, 
M. K. , and Bystrak, D. 1981. Effects of forest fragmentation on avifauna 
of the eastern deciduous forest. J_n R. L. Burgess and D. M. Sharp (eds.) 
Forest Island Dynamics in Man-Dominated Landscapes, p. 125-205. Ecological 
Studies 41, Springer-Verlag, New York, USA. 

Whittaker, R. H. 1956. Vegetation of the Great Smoky Mountains. Ecological 
Monographs 26: 1-80. 

Wilcox, B. A. 1978. Supersaturated island faunas: a species-age relationship 
for lizards on post-Pleistocene land-bridge islands. Science 199: 996-998. 



186 



MAMMALS OF THE SPRUCE-FIR FOREST IN 
GREAT SMOKY MOUNTAINS NATIONAL PARK 

Michael R. Pelton 



At the present time there are 60 species of mammals listed as likely 
occurring in Great Smoky Mountains National Park (Linzey and Linzey 1968) . 
The distributional range of 31 (52%) (16 of 17 possible families) is believed 
to encompass the spruce-fir vegetation zone of the Park (Table 1) . However 
22 (71%) have been reported from a wide range of elevations with only 9 species 
(29%) restricted to higher elevations and none totally restricted to the 
spruce-fir forest. Other species, particularly bats may occasionally occur 
in the spruce-fir but have not been reported to date. 

Mammals of the spruce-fir include 5 of 8 shrew species (Soricidae), 2 of 
3 moles (Talpidae) , 1 of 8 bats (Vespertilionidae) 2 of 2 rabbits (Leporidae) , 
5 of 7 squirrels (Sciuridae), 6 of 20 other rodents represented by native 
rats and mice (Cricetidae) , old world rats and mice (Muridae) , and jumping 
mice (Zapodidae) . All of the members of the order Carnivora (n = 9) with 
the exception of the skunks (Spilogale putorius and Mephitis mephitis) are 
represented in the spruce-fir; this includes the families Canidae, Ursidae, 
Procyonidae, Mustelidae, and Felidae. 

The relatively large home range and/or movement patterns of the larger 
mammals such as white-tailed deer ( Odocoileus virginianus ) , European 
wild hog ( Sus scrofa ) , and the Carnivora in general results in their 
occasional presence and/or use of the spruce-fir forest. However food or 
cover resources for many of these larger mammals often are limited in this 
vegetation type. For example there is little available or palatable food 
in the spruce-fir for white-tailed deer or European wild hogs. In the 
pure spruce-fir stands bears find few berries and no acorns. In addition 
the limited area of the spruce-fir and the occurrence of most of the smaller 
prey species (i.e. Cricetidae) in other, more extensive vegetation types in 
the Park, results in more limited use of the spruce-fir than other vegeta- 
tion types by carnivores. Consequently, the overall use of the spruce-fir 
zone by the larger mammals is oftentimes incidental compared to their use 
of other vegetation types. 

At the present time no definitive population data are available for any 
mammalian species in the spruce-fir forest. Although population studies 
have been conducted on a number of Park mammals including black bears ( Ursus 
americanus) (Pelton and Marcum 1975), white-tailed deer (Kiningham 1980), 
raccoons ( Procyon lotor ) (Keeler 1978, Rabinowitz 1981), woodchucks ( Marmota 
monax ) (Taylor 1979), striped skunks (Goldsmith 1981), and golden mice (Linzey 
1966), all such studies have been conducted in vegetation types other than the 



1. Professor, Department of Forestry, Wildlife, and Fisheries, The University 
of Tennessee, Knoxville, 1984. 



187 



spruce-fir. Data accumulated to date predominantly consist of general 
distributional records accumulated by various workers since the 1930 's 
(Komarek and Komarek 1938 and Linzey and Linzey 1968) . 

Even though the southern extension of the spruce-fir forest terminates 
in the Park, it appears that no single species is totally dependent on this 
vegetation type. 

Because so little is known about the population status of mammals 
residing or using the spruce-fir forest, the impacts of any significant 
vegetation change on mammal populations is unknown. Obviously, those 
species whose ranges are more closely associated with spruce-fir [i.e. 
masked shrew ( Sorex cinereous ) , long-tailed shrew ( Sorex dispar ) , Pigmy 
shrew ( Microsorex hoyi ) , Northern flying squirrel ( Glaucomys sabrinus ) 
and Rock vole ( Microtus chrotorrhinus ) ] are the ones that would be most 
significantly affected. Major disruptions of this area could have significant 
impacts on these species since most are at or near the southern extremity of 
their range in North America. Wind, fire, or insect damage in the spruce- 
fir create openings in the canopy and consequently new microhabitats ; these 
new habitats may then be beneficial or detrimental to certain mammals. 
Such openings and their new successional plant species may allow new mammal 
species to invade and/or cause a decline in resident animals, or result 
in an increase in some resident species. Successional vegetation may illicit 
a more resident species. Successional vegetation may illicit a more positive 
response from larger mammalian species whose presence had only been incidental 
in the past. Food plants in the form of berry crops or succulent browse 
attract bears, hogs, deer and raccoon. In addition a positive response of 
some small mammal populations to the altered conditions could result in more 
use of the spruce-fir habitat by mammalian predators. 

Future research efforts should concentrate on the status of the 9 
mammalian species restricted to higher elevations and specifically the 
5 species reportedly found only in the northern hardwood/spruce-fir forests 
of the Park. The status of the above 5 species should be evaluated on dis- 
turbed and undisturbed spruce-fir sites to assess the impacts of vegetation 
changes occurring. In addition the relative use or lack thereof by larger, 
more mobile mammals also should be assessed on these contrasting spruce-fir. 
sites . 

The spruce-fir forest is a logical selection for initiating future 
small mammal studies in the Park. It is a relatively restricted and well 
defined vegetation type, its southern terminus in North America occurs 
in the Park, and it is undergoing significant change at the present time. 

For more detailed information the readers are referred to Komarek and 
Komarek (1938), Kellogg (1939), and Linzey and Linzey (1968). The Park 
Library also contains the journal of Arthur Stupka, former naturalist and 
biologist for the Park (his journal covers the years 1935-1963) and a series 
of theses, dissertations and technical papers produced in the Department of 
Forestry, Wildlife, and Fisheries and Graduate Program in Ecology, The 
University of Tennessee, Knoxville from 1971 to present. 



188 



Table 1. Mammals occurring in the Spruce-fir forest of Great Smoky Mountains 
National Park. 



Family and Scientific Name 



Common Name 



General Range 



Didelphidae 

Didelphis virginiana 



Virginia opossum 



All elevations 



Soricidae 

Sorex cinereus 
Sorex fumeus 
Sorex dispar 
Microsorex hoyi 
Blarina brevicauda 



Masked shrew 
Smoky shrew 
Long-tailed shrew 
Pygmy shrew 
Short-tailed shrew 



Northern hardwoods 
and spruce-fir 

Mid. to higher 
elevations 

Northern hardwoods 
and spruce-fir 

Northern hardwoods 
and spruce-fir 

All elevations 



Talpidae 

Parascalops brewer i 
Condylura cristata 



Hairy-tailed mole 
Star-nosed mole 



All elevations 
All elevations 



Vespertilionidae 

Eptesicus fuscus 



Big brown bat 



All elevations 



Leporidae 



Sylvilagus floridanus Eastern cottontail 
Sylvilagus transitional is New England cottontail 



All elevations 
All elevations 



Sciuridae 

Sciurus carol inensis 
Marmota monax 
Tamias striatus 
Tamiasciurus hudsonicus 



Gray squirrel 
Woodchuck 
Eastern chipmunk 
Red Squirrel 



All elevations 

All elevations 

All elevations 

All elevations 



189 



Table 1. (Continued - page 2) 



Family and Scientific Name Common Name 



General Range 



Cricetidae 



Peromyscus maniculatus 
Clethrionomys gapperi 



Deer mouse 

Gapper's red-backed mouse 



Microtus chrotorrhinus Rock vole 



All elevations 
Mid to higher 

elevations 
Northern hardwood and 

spruce fir 



Muridae (Old World Rats and Mice) 



Rattus norvegicus 
Rattus rattus 



Norway rat 
Black rat 



All elevations 
All elevations 



Zapodidae (Jumping mice) 

Napaeozapus insignis Woodland jumping mouse 



All elevations 



Canidae 



Vulpes vulpes Red fox 

Urocyon cinereoargenteus Gray fox 



All elevations 
All elevations 



Ursidae 

Ursus americanus 



Black bear 



All elevations 



Procyonidae 

Procyon lotor 



Raccoon 



All elevations 



Mustel idae 

Mustela frenata 
Mustela vison 



Long-tai led weasel 
Mink 



All elevations 
All elevations 



190 



Table 1. (Continued - page 3) 



Family and Scientific Name Common Name General Range 

Felidae 

Lynx rufus Bobcat All elevations 

Suidae 

Sus scrofa European wild hog All elevations 

Cervidae 

Odocoileus virginianus White-tailed deer All elevations 



Summarized from Linzey and Linzey (1971). 



191 



LITERATURE CITED 

Goldsmith, D.M. 1981. The ecology and natural history of striped skunks 

in the Cades Cove campground, Great Smoky Mountains National Park, 
Tennessee. M.S. Thesis, The Univ. of TN, Knoxville. 77 pp. 

Keeler, W.E. 1978. Some aspects of the natural history of the raccoon 

( Procyon lotor ) in Cades Cove, The Great Smoky Mountains National 
Park. M.S. Thesis, The Univ. of TN, Knoxville. 81 pp. 

Kellogg, R. 1939. Annotated list of Tennessee mammals. Proc. U.S. Nat. 
Mus. 86 (3051): 245-303. 

Kiningham, M.J. 1980. Dnesity and distribution of white-tailed deer 

( Odocoileus virginianus ) in Cades Cove, Great Smoky Mountains National 
Park, Tennessee. M.S. Thesis, The Univ. of TN, Knoxville. 93 pp. 

Komarek, E.V., and R. Komarek. 1938. Mammals of the Great Smoky Mountains. 
Bull. Chicago Acad. Sci. 4(6) :137-162. 

Linzey, D.W. 1966. The life history, ecology, and behavior of the golden 
mouse, Ochrotomys nuttalli in the Great Smoky Mountains National 
Park. Ph.D. Thesis. Cornell Univ., Ithaca, NY 176 pp. 

Linzey, D.W., and A.V. Linzey. 1968. Mammals of the Great Smoky Mountains 
National Park. J. Elisha Mitchell Sci. Soc . 84(3) :384-414 . 

Linzey, A.V. and D.W. Linzey, 1971. Mammals of Great Smoky Mountains National 
Park. The Univ. of Tennessee Press. 114 pp. 

Pelton, M.R., and L. C. Marcum. 1975. The potential use of radioisotopes 
for determining densities of black bear and other carnivores, 
pp. 221-236. In: Proc. Pred. Symp. R.L. Phillips and C. Jonkel, 
eds. Montana Forest and Conservation Experiment Sta., Univ. of 
Montana, Missoula. 268 pp. 

Rabinowitz, A.R. 1981. The ecology of the raccoon ( Procyon lotor ) 

in Cades Cove, Great Smoky Mountains National Park. Ph.D. Dissert., 
The Univ. of Tennessee, Knoxville. 133 pp. 

Taylor, C.A. 1979. The density, distribution, and activity patterns of 
woodchucks in Cades Cove, Great Smoky Mountains National Park. 
M.S. Thesis, The Univ. of Tennessee, Knoxville. 73 pp. 



192 



DISTRIBUTION AND STATUS OF THE NORTHERN FLYING 
SQUIRREL AND THE NORTHERN WATER SHREW 
IN THE SOUTHERN APPALACHIANS 



Donald W. Linzey 



Abstract . — The northern flying squirrel and northern water 
shrew exist in disjunct, relict populations in the southern Appa- 
lachians. Only 27 specimens of the northern flying squirrel from 8 
localities in the southern Appalachians exist in collections. A 
recently completed two year study involved the placement of 490 
nest boxes in high elevation habitat throughout a five state study 
area. The study resulted in this species being rediscovered on Mt. 
Mitchell after not having been recorded there for 31 years. No 
specimens have been recorded in the Great Smoky Mountains National 
Park since 1958 (24 years) nor from Whitetop Mountain in Virginia 
since 1966 (17 years). Habitat destruction, interspecific competi- 
tion with the smaller, more aggressive southern flying squirrel, 
and infection by a parasitic nematode have been proposed as pos- 
sible causes of the decline of this species. A survey to determine 
the status and distribution of this species is recommended. 

Only 50 specimens of the northern water shrew from 10 locali- 
ties exist in collections. These shrews have been taken from two 
new areas in the Great Smoky Mountains National Park. These speci- 
mens represent a new watershed record and a low elevation record. 
One population in existence in 1950 and 1965 was apparently gone in 
1980. This species is currently known to inhabit only two locali- 
ties in the Park. Additional population studies are recommended. 

Additional keywords : Endangered species, Sorex palustris , Glaucomys 
sabrinus. 



INTRODUCTION 

The mammalian fauna of the southern Appalachians is diverse, ranging 
in size from the pygmy shrew to the black bear. Some species are widespread 
in distribution, whereas others inhabit only specific portions of the region. 
Those species with restricted ranges are, in many cases, the species which are 
increasingly being classified as rare, threatened, or endangered due in large 
part to modifications and/or elimination of their habitat. 



Among the 60 or so species of mammals currently inhabiting the Great 
Smoky Mountains National Park, several have been recorded from only two or 
three localities. Some of these species reach the northernmost limit of their 



1/ Consulting Biologist, 2101 Nellies Cave Road, Blacksburg, Virginia 24060 



193 



range in the Smokies (rice rat, cotton rat). Others prefer cultivated areas 
and fields which are becoming increasingly more scarce in the Park as succes- 
sion proceeds. A few of these rare species reach the southernmost limit of 
their range in the Smokies. Such species are common in more northern states 
and in Canada, but in the southern Appalachians these species exist only in 
isolated, relict populations. Two species with restricted ranges which fall 
into this category are the northern flying squirrel ( Glaucomys sabrinus ) and 
the northern water shrew ( Sorex palustris ) . 



RANGE AND HABITAT OF FLYING SQUIRREL 



The northern flying squirrel is represented in the southern Appalachians 
by two subspecies. Glaucomys sabrinus fuscus ranges from western Maryland 
south through West Virginia to southwestern Virginia. The range of Glaucomys 
sabrinus coloratus extends from southwestern Virginia south to the southern 
limit of the species' range in Tennessee and North Carolina. The subspecies 
fuscus has been recorded in West Virginia from Pocahontas and Randolph coun- 
ties (Miller, 1936; Handley, 1953) and in Virginia from Smyth County (Handley, 
In : Linzey, 1979). The southern subspecies coloratus is known from only three 
localities. It has been taken in Yancey County, North Carolina (Handley, 
1953) and in Sevier and Carter counties, Tennessee (Kellogg, 1939; Handley, 
1953; Linzey and Linzey, 1971). Only 27 specimens and records of this species 
from 8 localities in the southern Appalachians exist in college, university, 
museum, and private collections. Seven are from West Virginia, one is from 
Virginia, four are from North Carolina (near Mt. Mitchell), and 15 are from 
Tennessee (13 from Roan Mountain, 2 from the Great Smoky Mountains National 
Park) . 

Both forms of flying squirrel are generally restricted to areas con- 
taining spruce and fir and to high elevation stands of hardwoods such as 
beech, birch, and maple. The hollows of large, old yellow birch trees in the 
ecotone between the spruce-fir forest and the northern hardwood forest provide 
many nesting cavities. Most records in the southern Appalachians are above 
4000 feet elevation. The diet of these squirrels consists mostly of lichens, 
fungi, seeds, buds, fruit, and insects. 

Glaucomys sabrinus fuscus may occur in the George Washington and Jeffer- 
son National Forests, while Glaucomys sabrinus coloratus may occur in the 
Jefferson, Pisgah, and Cherokee National Forests. The northern flying squir- 
rel has been classified as Endangered in Virginia (Handley, In: Linzey, 
1979), Threatened in North Carolina (Cooper, Robinson, and Funderburg, 1977), 
Deemed In Need of Management in Tennessee (Eagar and Hatcher, 1980), and Rare 
and Of Scientific Interest in West Virginia. 

Only two specimens of the northern flying squirrel have ever been taken 
in the Park. One of these was taken in 1935 on Blanket Mountain southwest of 
Elkmont at an elevation of 4000 feet. In 1959, a nursing female was found 
dead on the road near Walker Prong. These squirrels have never been seen on 
Mt . LeConte or Clingman's Dome. 



194 



CURRENT STATUS OF FLYING SQUIRREL 

A two year study of these species in the southern Appalachians has 
recently been completed. The study was jointly funded by the Office of Endan- 
gered Species of the U. S. Fish and Wildlife Service and Virginia Polytechnic 
Institute and State University. The study was a direct outgrowth of the 
Symposium on Endangered and Threatened Plants and Animals of Virginia which I 
organized in 1978 and for which I subsequently served as Editor of the Pro- 
ceedings (Linzey, 1979). The study involved the distribution and status of 
these two mammals in parts of five states - Maryland, Virginia, West Virginia, 
North Carolina, and Tennessee. 

To study the flying squirrel, we constructed nest boxes with sliding 
doors. A total of 490 nest boxes were erected in suitable high-elevation 
habitat throughout the study area. All boxes were checked periodically. We 
have boxes, for example, on Grandfather Mountain, Roan Mountain, Mt . Mitchell, 
and along the Blue Ridge Parkway. Here in the Smokies, I have 40 nest boxes 
in five areas from Newfound Gap to Clingman's Dome and in two areas on Balsam 
Mountain. 

The nest boxes have been used primarily by southern flying squirrels 
( Glaucomys volans ) and red squirrels ( Tamiasciurus hudsonicus ) . Several 
litters of flying squirrels and red squirrels have been reared in the boxes. 

Several northern flying squirrels have also been taken. One nest box on 
Mt . Mitchell yielded an adult male and an adult female northern flying squirrel 
the first specimens of this species observed there since 1950, a period of 31 
years. We have recorded other specimens in West Virginia. In the Smokies, 
however, I have been unsuccessful in finding any recent evidence of this 
species. Some nest boxes contain a few seeds or pieces of bark, but nothing 
in the way of nests as in most other localities. This does not necessarily 
mean that the northern flying squirrel has now been extirpated from the Park, 
but if they still do exist, their numbers must be minimal. 

A similar situation exists in the Whitetop-Mt. Rogers-Pine Mountain area 
of southwestern Virginia. The only two specimens ever recorded from Virginia 
were taken on Whitetop in 1959 and 1966. Approximately 70 nest boxes have 
been erected in this area, but no northern flying squirrels have been taken. 

Habitat destruction from clear cutting, certain forest management prac- 
tices, and recreational development may have adversely affected some popula- 
tions in the southern Appalachians. In addition, there is some evidence that 
interspecific competition between the northern and southern flying squirrel 
may be affecting the range of the former species. Although range maps show a 
broad zone of sympatry, in reality there is surprisingly little actual overlap 
in the ranges of these two species. Areas may be inhabited by one or the 
other of these marginally sympatric species at any given time, but not by both 
at the same time. The species' ranges in the overlap zone appear to be 
highly variable and often exclusive. Research has indicated that the larger 
northern flying squirrel may be displaced by the more aggressive, smaller 
southern flying squirrel in certain hardwood habitats where their ranges meet. 
In some areas, the southern flying squirrel has been taken near several sites 
where the northern flying squirrel had previously been recorded. There is also 
some evidence that the southern flying squirrel harbors a parasitic nematode of 

195 



the genus Strongyloides which may be transferred to the northern flying squirrel 
in areas where their ranges meet and overlap, and is lethal or debilitating 
(Weigl, 1977). 

In Virginia, Handley (1979) noted: "Very likely, the numbers and range of 
the northern flying squirrel in the southern Appalachains have been shrinking 
as climate and habitat have changed ever since the Pleistocene. Even before 
the arrival of European settlers these processes probably had fragmented its 
range in the mountains of Virginia into relict segments. Logging and clearing 
for other land use and the consequent invasion of its habitat by the southern 
flying squirrel undoubtedly have accelerated the decline of the northern flying 
squirrel in the past two hundred years. It must now be on the verge of extinc- 
tion in Virginia." 

Handley (1979) further noted: "In Virginia, Glaucomys volans now occurs 
to the tops of the highest mountains and occupies the best remnants of habitat 

suitable for Glaucomys sabrinus The future looks bleak, indeed, for 

Glaucomys sabrinus in Virginia." 

Speciation tends to occur most commonly near the periphery of a species' 
range as populations, for one reason or another, become isolated from each 
other. The relict populations of northern flying squirrels seem to be becoming 
increasingly isolated. This isolation can effectively prevent the free flow of 
genes among other members of the species. These geographical isolates eventu- 
ally become recognized as distinct races or subspecies. This situation has 
already resulted in the naming of two subspecies of northern flying squirrel in 
the southern Appalachians. If viable populations continue to exist, further 
speciation may be expected. 

MANAGEMENT RECOMMENDATIONS 

Concerning Tennessee, Eagar and Hatcher (1980) stated: "A natural history 
survey is needed to establish the actual status of G_. sabrinus in Tennessee and 
to provide information necessary in order to implement proper management 
measures. Lands with suitable habitat should not be disturbed, and more land 
acquisition should be urged by state and federal agencies." ' 

For North Carolina, Weigl (1977) noted: "Additional research is needed on 
the Northern Flying Squirrel in the southern parts of its range before 
precise protective measures can be proposed. Preservation of high elevation 
forests and bogs, including bothspruce-f ir stands and adjacent zones of 
northern hardwood vegetation, is a necessity." 

In Virginia, Handley (1979) stated: "Suitable habitats should be more 
thoroughly explored for Glaucomys sabrinus . If populations of this squirrel 
are found, an effort should be made to prevent further alteration of its habi- 
tat." 

In order to determine the distribution and status of this species in the 
Park, an expansion of the existing network of nest boxes is recommended. 
Although considerable effort is required to construct, erect, and monitor these 
nest boxes on a regular basis, the cost of materials is minimal. A 24 month 
study should provide sufficient data to determine the status of this species in 



196 



the Park. Since the Blanket Mountain locality represents the southernmost 
locality for this species, every effort should be made to ascertain whether 
viable populations still remain within the protective confines of the Park. 



RANGE AND HABITAT OF WATER SHREW 

The northern water shrew is represented in the southern Appalachians by a 
single subspecies, Sorex palustris punctulatus . The range of this form extends 
from western Maryland south through West Virginia and western Virginia to 
Tennessee and North Carolina. Only 50 specimens and records of this species 
from 10 localities in the southern Appalachians exist in college, university, 
museum, and private collections. Nine are from West Virginia, one is from 
Virginia, five are from North Carolina, and 33 are from Tennessee (17 from the 
Cherokee National Forest and 16 from the Great Smoky Mountains National Park) . 
It has been recorded in West Virginia from Preston, Randolph, Pendleton, and 
Tucker counties by Hooper (1942) and McKeever (1952) . The only specimens ever 
recorded from Virginia were from Bath County (Pagels and Tate, 1976). Conaway 
and Pfitzer (1952) and Linzey and Linzey (1968; 1971) recorded this species in 
the Great Smoky Mountains National Park. Prior to 1980, the water shrew was 
known in North Carolina from only four specimens taken along Fires Creek in 
Clay County in 1973 (Whitaker, Jones, and Pascal, 1975). 

In the southern Appalachians, Sorex palustris lives along the banks of 
swiftly flowing, rocky-bedded mountain streams, usually above 3000 feet eleva- 
tion. They swim in the cold water in search of immature aquatic insects. 
Dominant vegetation may be spruce, fir, hemlock, willow, yellow birch, and 
rhododendron. The water shrew may occur in the George Washington, Jefferson, 
Pisgah, and Cherokee National Forests. Due to the paucity of data concerning 
the status and distribution of this shrew, it has been designated as Endangered 
in Virginia (Handley, In: Linzey, 1979), Status Undetermined in North Carolina 
(Cooper, Robinson, and Funderburg, 1977), Deemed in Need of Management in 
Tennessee (Eagar and Hatcher, 1980), and Rare and Of Scientific Interest in 
West Virginia. 

It was not until 1950 that this species was recorded as a member of the 
Park fauna. In that year, Conaway and Pfitzer took several individuals along 
Walker Prong of the Little Pigeon River less than a mile below the confluence 
with Alum Cave Creek. These specimens represented a new state record for 
Tennessee. They also represented a southward range extension of 200 miles from 
a site in West Virginia. They have since been found living beneath overhanging 
banks and in rock crevices along Walker Prong and other tributaries of the 
Little Pigeon River from 3700 feet to 4700 feet elevation. 



CURRENT STATUS OF WATER SHREW 

The second part of the study for the U. S. Fish and Wildlife Service 
involved the northern water shrew. To study this species, Sherman live traps 
baited with potted meat were used. Traps were set in suitable habitat through- 
out the five state study area. Within the Park, trapping was carried out along 

197 



such waterways as Walker Prong, Kanati Fork, Beech Flats Creek, the Oconaluftee 
River, Bunches Creek, Cosby Creek, and several areas in the Greenbrier section 
including the Middle Prong of the Little Pigeon River and Porter's Creek. 

In 1965, I was successful in rediscovering these shrews along Walker 
Prong. However, no specimens appeared to be present during 1980. Extensive 
trapping was conducted along Beech Flats Creek in 1965, but no shrews were 
taken. In 1980, however, one specimen was secured at an elevation of approxi- 
mately 4000 feet. This record is especially significant because it represents 
the first record of this species in the North Carolina section of the Park and 
the first record for the Deep Creek watershed. It is only the second record of 
this species from the state of North Carolina. Also In 1980, a specimen was 
taken along a tributary of the Middle Prong of the Little Pigeon River near 
Ramsey Cascades. This record was unique because the specimen was taken at an 
elevation of between 1925 and 2000 feet and represents the lowest elevation on 
record for this species in the southern Appalachians. It significantly expands 
the area that could be inhabited by this species and that should be searched 
for its presence. 

The problem of isolated populations and speciation addressed in the flying 
squirrel account holds true for the water shrew as well. 



MANAGEMENT RECOMMENDATIONS 

At the present time, the northern water shrew is known to be living in 
only two small areas within the Park. Although further trapping would un- 
doubtedly reveal a more widespread distribution, the small, isolated popula- 
tions would continue to be vulnerable. Since these areas are within a National 
Park, they will probably not undergo sudden alterations, but if any changes are 
planned, a thorough investigation should be made to determine whether water 
shrews are present. 

The situation in the Park is obviously unique. Elsewhere the situation is 
quite different. In Virginia, for example, the water shrew has been taken at 
only one locality. It was discovered during the environmental survey for 
Virginia Electric Power Company's huge pumped storage reservior project in Bath 
County (Pagels and Tate, 1976). This project is now approximately two-thirds 
complete and the shrew habitat has been completely destroyed. Thousands of 
trap nights in nearby areas and surrounding counties have failed to reveal the 
presence of any other populations. Extensive logging operations in West Virginia 
have the capacity to destroy considerable habitat for this species. Lowman 
(1975) noted that siltation caused by logging operations, off-road vehicles, 
and road construction can destroy mountain streams as suitable habitat for 
water shrews, as well as human waste, trash, and garbage from improperly located 
camping areas. Three new ski resorts are planning to begin operations during 
the latter part of 1983 in West Virginia. The construction of buildings and 
roads associated with these resorts could be extremely detrimental to shrew 
populations inhabiting these areas. 

The precise distribution and abundance of this shrew within the southern 
Appalachians remains unknown. In Virginia, Handley (1979) stated: "It seems 
likely that the water shrew no longer occurs at the single locality where it 



198 



has been found in Virginia It is possible that other surviving isolated 

populations will be found, but at best numbers must be very low The 

remnants should be jealously protected." In addition, he proposed the follow- 
ing protective measures: "If there are remnant populations of water shrews to 
be protected in Virginia, they first must be located. Then it will be necessary 
to protect inhabited streams from clearing, siltation, pollution (particularly 
with insecticides), and other destructive disturbance." 



CONCLUSION 

The disjunct, island-like distribution of these three forms and their 
great distance from the center of their species' range in the northern United 
States and Canada suggest that they are relict forms which have become isolated 
in small patches of suitable habitat by changing climatic and vegetational 
conditions since the last glacial period of the Pleistocene. Handley (1971) 
noted that disjunctions in their ranges probably could be accounted for by 
irregularities in elevation of the mountains and oscillations in temperature. 

The small, isolated populations of these forms in the southern Appala- 
chians deserve protection. There is little we can do about natural climatic and 
vegetational changes. However, we can and should provide protection from such 
human activities as logging, bulldozing, siltation, and pollution. Our initial 
efforts need to concentrate on locating additional populations. 



LITERATURE CITED 



Conaway, C. H. and D. W. Pfitzer. 1952. Sorex palustris and Sorex dispar 
from the Great Smoky Mountains National Park. J. Mamm. 33:106-108. 

Cooper, J.E. , S. S. Robinson, and J. B. Funderburg (editors). 1977. Endangered 
and Threatened Plants and Animals of North Carolina. North Carolina State 
Museum of Natural History, Raleigh. 444 pp. 

Eagar, D. C. and R. M. Hatcher. 1980. Tennessee's Rare Wildlife. Volume I: 

The Vertebrates. Tennesssee Wildlife Resources Agency, Nashville. 356 pp. 

Handley, C. 0., Jr. 1953. A new flying squirrel from the southern Appalachian 
Mountains. Proc. Biol. Soc. Wash. 66:191-194. 

1971. Appalachian mammalian geography — Recent Epoch Pp. 

263-303. In: Holt, P. C. (editor). The Distributional History of the 
Biota of the Southern Appalachians. Part III. Verebrates. Virginia 
Polytechnic Institute Research Division Monograph 4. 

1979a. Water shrew. Pp. 490-491. In: Linzey, D. W. 



(editor) . Proceedings of the Symposium on Endangered and Threatened Plants 
and Animals of Virginia. Virginia Polytechnic Institute and State Univer- 
sity, Blacksburg. 665 pp. 



199 



1979b. Northern flying squirrel. Pp. 513-516. In: Linzey , 

D. W. (editor). Proceedings of the Symposium on Endangered and Threatened 

Plants and Animals of Virginia. Virginia Polytechnic Institute and State 
University, Blacksburg. 665 pp. 

Hooper, E. T. 1942. The water shrew ( Sorex palustris ) of the southern Allegheny 
Mountains. Occas. Pap. Mus. Zool., Univ. Michigan 463:1-4. 

Kellogg, R. 1939. Annotated list of Tennessee mammals. Proc. U. S. Nat. Mus. 
86:245-303. 

Linzey, A. V. and D. W. Linzey. 1971. Mammals of Great Smoky Mountains National 
Park. University of Tennessee Press, Knoxville. 114 pp. 

Linzey, D. W. (editor). 1979. Proceedings of the Symposium on Endangered and 
Threatened Plants and Animals of Virginia. Virginia Polytechnic Institute 
and State University, Blacksburg. 665 pp. 

and A. V. Linzey. 1968. Mammals of the Great Smoky Moun- 



tains National Park. J. Elisha Mitchell Sci. Soc. 84:384-414. 

Lowman, G. E. 1975. A survey of endangered, threatened, rare, status undeter- 
mined, peripheral, and unique mammals of the southeastern National Forests 
and Grasslands. USDA, Forest Service, Southern Region. 

McKeever, S. 1952. A survey of West Virginia mammals. West Virginia Cons. 
Comm. , Pittman-Robertson Project 22-R. 126 p. (mimeographed) 

Miller, G. S., Jr. 1936. A new flying squirrel from West Virginia. Proc. 
Biol. Soc. Wash. 49:143-144. 

Pagels, J. F. and C. M. Tate. 1976. Shrews (InsectivorarSoricidae) of the 

Paddy Knob-Back Creek area of western Virginia. Va . J. Sci. 27:202-203. 

Weigl, P. D. 1977. Northern flying squirrel. Pp. 398-400. In: Cooper, J. E. , 
S. S. Robinson, and J. B. Funderburg (editors). Endangered and Threatened 
Plants and Animals of North Carolina. North Carolina State Museum of Natural 
History, Raleigh. 

Whitaker, J. 0., Jr., G. S. Jones, and D. D. Pascal, Jr. 1975. Notes on mammals 
of the Fires Creek Area, Nantahala Mountains, North Carolina, including 
their ectoparasites. J. Elisha Mitchell Sci. Soc. 91(1):13-17. 



200 



SOILS IN THE SPRUCE-FIR REGION OF THE GREAT SMOKY MOUNTAINS 

1 
M. E. Springer 

Abstract. Schematic diagrams were used to relate kinds ot soil to 
e I evat ion , aspect, parent material, and vegetation. Mean annual soil 
temperatures are superimposed on these diagrams. Also, a simplified 
diagram predicted Spodosols or Inceptisols under four combinations of 
spruce-fir and northern hardwood vegetation with coarse and fine textured 
parent material. Soils were unstable because of tree throw, creep, and 
landslides, but general patterns were predictable. 

At high elevations, all the soils were low in base saturation and 
extremely acid. Major vegetation types were ranked in the following 
sequence of decreasing pH of the horizon: northern hardwoods, spruce- 
fir, heath bald. This sequence was also a gradient of increasing 
distinctness of horizons and depth of horizon layers. 

INTRODUCTION 

Soils of the spruce-fir region at elevations of 1500 to 1900 m in the 
Smoky Mountains are similar to those of spruce-fir regions farther north in 
the Appalachians but differ from soils at nearby lower elevations where 
conditions are warmer and dryer. Surveys and research studies in Great Smoky 
Mountains National Park (GRSM) and other parts of the Unaka mountains indicate 
that at high elevations all the soils are extremely acid and low in base 
saturation. They are mainly Inceptisols with lesser areas of Spodosols. 
Schematic diagrams relate the kind of soil to elevation, aspect, parent 
material, and vegetation. However, more precise information on the nature and 
location of the different soils is needed for decisions in management research. 

LITERATURE REVIEW 

Coile (1938) described well-defined Podzols in West Virginia and in 
Tazewell County, Virginia, and less we I I -deve I oped Podzols at elevations above 
1400 or 1500 m in southwestern North Carolina and eastern Tennessee. Near a 
Podsol in West Virginia, he described a brown forest soil under northern 
hardwood forest type and suggested that "The two contrasting types of soil, 
developed along the tension zone of the red spruce and birch-beech-maple forest 
types are believed to have been influenced in their development primarily by 
the widely different forest vegetation types." 

Early soil surveys of Cocke (1955), Sevier (1956), and Blount (1959) 
Counties in Tennessee classified the spruce-fir region as Ramsey or Ashe soils 
and stony rough I ands or rough mountainous land. Soils were described as 
strongly acid and low in fertility. A survey of Swain and Haywood Counties 
in North Carolina, listed the soils as Burton, Porters, and Ramsey. 
Delineation of the different soils was too general for detailed research 
management . 



Professor Emeritus, Department of Plant and Soil Science, University of 
Tennessee, Knoxville, Tenn. 



201 



At 1580 m, McGinnis (1958) reported that in the layers under spruce- 
fir, organic matter of 98,000 kg/ha was 14 times greater than under beech gap 
forest. However, in the mineral soil under spruce-fir, organic matter content 
of 151,000 kg/ha was only slightly more than under beech gap. Concentration 
of Ca and pH values were less under spruce-fir. 

Properties of soils at elevations from 1370 to 2000 m in the Great Smoky 
Mountains were reported by McCracken et al. (1962). They grouped the soils 
into those "lacking A2 horizons with thin Al and 'color B' horizons" and 
others "with A2 horizons, Bir horizons, and relatively thick mor layers." 
Soils of the first group were described on well drained sites under both 
spruce-fir and northern hardwood vegetation and were ascribed to the Sols 
Bruns Acides great soil group. The second group described on "less we I I - 
drained sites under heath bald or rhododendron understory of spruce-fir, with 
some indication that they tend to form from more quartzose conglomeratic rock" 
were interpreted as Podzols. They emphasized that the prevailing soils at 
higher elevations in the Smoky Mountains as represented by two of their soils 
are "characterized by duff mull surficial horizons, relatively thick and 
granular Al horizons, and B horizons differentiated by color but not by 
relative accumulation of layer silicate clay or of iron. They are extremely 
weathered, are very low in base status and show surface incorporation of 
organic carbon which decreases with depth." 

Over feldspathic sandstone and under spruce-fir in GRSM, Wolfe (1967) 
suggested that three soils appeared to represent Umbric Dystrochrepts , 
incipient Spodosols, and Spodosols. He compared these with soils from medium- 
textured parent material and those under beech gap vegetation. Soils under 
both kinds of vegetation are highly acid and low in base saturation. Exchange 
acidity was greater in soils under spruce-fir than under adjacent beech stands, 
but decreased with depth under both. Under heath vegetation, pHw values were 
even less. Wolfe suggested that bedrock differences were not responsible for 
sudden changes in vegetation. Leaf litter produced by beech was less acid, 
contained slightly more bases, and formed looser, less persistent layers of 
organic matter than did the spruce-fir litter. Roots were distributed to 
greater depths and soil horizons were less distinct under beech. 

In the Balsam Mountains, Weaver (1972) recognized Inceptisols only, even 
though parent materials were mica-gneiss and mica schists and soils were 
somewhat coarser than in the Smokies. Concentration of Ca in the forest floor 
under yellow birch was two or three times higher than under spruce-fir, 
although there was little difference in total content. By treating forest 
floor apart from the soil, he suggested that vegetation and the forest floor 
are the major nutrient sinks and the proportion in the soil is generally low. 
Nutrients in the litter fall are returned at rates of one kg/40-60 kg in 
yellow birch stands and one kg/90-100 kg in spruce-fir stands. 

Springer and Elder (1980) generalized the soils of the spruce-fir region 
of GRSM with the steep and very steep loamy and stony soils at high elevations 
from metamorphic and igneous rocks and colluvium (Dystrochrepts, Hap I umbr ep t s , 
Spodosols). They stated "The soils are loamy, vary in content of stones, and 
range from shallow on the crests and upper slopes of the mountains to deep on 
the long talus slopes with thick accumulations of downslope creep. Most of 
the surface layers, especially on north facing slopes, are dark and high in 

202 



organic matter. On the lofty peaks, temperatures are cool, annual 
precipitation is 60 to 80 inches (150-200 cm), vegetation is heath or 
coniferous, and some of the soils have a highly bleached layer beneath an 
organ i c I ayer . " 

They placed the Tennessee part of the GRSM spruce-fir region in Ditney 
Jef f rey-Brooksh i re : Steep and very steep, shallow to deep, loamy and stony 
soils from sandstone, graywacke, schist, slate, and colluvium. In describing 
the soils they state that rocks high in weatherable minerals make up the bed 
rock. "Because of the high altitude and cool climate most of the soils have 
dark surface layers high in organic matter. The soils range from I to 3 feet 
(0.3 - I m) deep on the crests and upper parts of the mountain slopes to as 
much as 7 or 8 feet (2 m) deep in coves and on the lower slopes of mountains 
where there are thick accumulations of downslope creep. The soils vary in 
stone content and have loamy permeable subsoils. 

"Ditney and Jeffrey soils are on the upper slopes of the mountains. 
Jeffrey soils are higher and darker than Ditney soils. Brookshire and Sp i vey 
soils are in the coves and on the lower parts of the slopes where thick 
deposits of colluvium have accumu I ated . . . . The soils are loamy, mixed Umbric 
and Typic Dyst rochrep ts , with small areas of loamy, mixed Haplumbrepts and 
Spodosols at the highest elevations." 

Their description of Tennessee soils north of GRSM is applicable to some 
of the North Carolina part of the spruce-fir region. A description of Unaka- 
Ashe : Steep and very steep, deep and moderately deep, loaming and stony so i Is 
from gneiss, granite, and colluvium, follows. "The soils formed from these 
rocks or from downslope creep. They are well drained, loamy, and friable from 
the surface to bedrock and contain few to common fragments of granite and 
gneiss. Soil thickness ranges from I to 4 feet (0.3 to 1.2m) on the upper 
slopes to more than 6 feet (2 m) on the lower slopes and in coves. In many 
places the upper few feet of the bedrock are weathered or softened to 
saprolite. Small flakes of mica are common throughout the soils. At the 
lower elevations the soils have pale surface layers, but the surface layers 
are darker at elevations above 3000 to 4000 feet (900 to 1200 m), especially 
on the north- and east-facing slopes. The soils are medium acid and strongly 
acid and moderately high in natural f er t i I i ty . . . . The soils are loamy, mixed 
Umbric and Typic Dystrochrep ts with some loamy, mixed Haplumbrepts and 
Spodoso Is." 

In a soil survey of Monroe County, Tennessee, Ha I I et al. (1981) delineated 
and described soils comparable to those under northern hardwoods in GRSM. 
Citico, Sylco, and Ditney are Typic Dystrochrep ts . Sp i vey is a Typic 
Haplumbrept. Brookshire and Jeffrey are Umbric Dystrochrept s . 

DISCUSSION 

With results of research in the literature as background, numerous 
transects from the spruce-fir region to lower elevations reveal patterns that 
relate soils to parent material, aspect, elevation, and vegetation. The most 
probable kinds of soil at different elevations and aspects are indicated by 
Figures I to 3. The dashed lines show that annual soil temperatures decline 
as elevation increases and are lower in sheltered than in exposed positions. 

203 



In the Great Smoky Mountains, greater rainfall at high elevation also adds to 
the moister conditions. Figure I shows that soils are darker colored and 
higher in organic matter in the cooler and wetter conditions at high 
elevations and sheltered positions. With exposure and decreasing elevations, 
surface horizons are lighter colored, and clay content in B horizons is 
greater . 

If parent material is coarse and the soil surface is stable, leaching 
through the organic layer under spruce-fir produces bleached E horizons and 
Bh or Bir horizons in the mineral soil (Figure 2). Nearby, under northern 
hardwoods or under unstable conditions in spruce-fir, horizons are less 
d i st i net . 

Under rhododendron or other heath vegetation, organic layers are thicker, 
acidity is greater, and soil horizons are more distinct than under either 
spruce-fir or northern hardwoods. Spodoso I s are far more common and may 
extend to elevations as low as 1000 m (Figure 3). In places, organic layers 
are so thick that the soils are Histosols. 

Above 1500 m, Inceptisols are by far the most common, but the kind of 
Inceptisols and the presence of Spodosols form a predictable pattern. A 
simplified vegetation-soil relationship for stable topography at 1700 m 
(Figure 4) relates kind of soil to parent material and vegetation. Where 
parent material was medium textured, both northern hardwoods and spruce-fir 
are on Inceptisols. Under northern hardwoods, the organic distribution is 
mull type. Under spruce-fir it is mor . Where parent material was coarse, 
Spodosols with distinct organic and mineral horizons are under the spruce-fir. 
Adjoining these under northern hardwoods, horizons are less distinct, organic 
distribution is mull type, and the soils are mainly Umbric Dys t rochrep t s or 
Umbrepts. Tree-throw, creep, landslides, and changing vegetation are 
continually shifting these patterns. 

In the spruce-fir region the geological maps and tremendous amount of 
ecological information can be related to fragmentary knowledge of soils. Where 
either research or intensive management is conducted, more precise location 
of the soils by detailed surveys is definitely needed. In other areas, at 
least semidetailed soil maps would help relate soils to other parts of the 
environment as a basis for wiser management. 

A few studies that deserve priority are: 

1. Delineate and classify the different kinds of soil and display them 
on a soil map. Survey critical areas in detail. Use the results in 
preparation of a general soil map of the whole park. 

2. Relate natural runoff and leachate to kind of soil and kind of 
vegetation; e.g., heath versus northern hardwood, heath versus cove hardwood. 

3. Coordinate soils with research in other disciplines. 

k. Relate natural runoff and leachate to kind of soil and kind of vegetation 
eg. heath vs. northern hardwood, heath vs. cove hardwood. 



204 



SUMMARY 

At high elevations, all the soils are low in base saturation and 
extremely acid. Under different vegetation, pH of the horizons ranks 
northern hardwoods > spruce-f i r > heath . Distinctness of horizons and 
thickness of layers is in the order: northern hardwoods < spruce-fir 
heath . 



205 



Figure 1 . Soils patterns of the Great Smoky Mountains — 
Medium textured parent material or unstable 
surface (heath vegetation excepted) 



6500 - 

6000 - 








C 

<y 

•H 
T3 

a 
u 




a 

c 
o 

•P 

> 

w 



6000 k 

5500 

5000 



• • 



••< 



,••' 



,••' 



UMBREPTS 




Moisture Gradient 
Annual soil temperatures are shown by thin dashed lines 



206 



Figure 2. Soils patterns of the Great Smoky Mountains — 
Coarse textured parent material and stable 
surface (heath vegetation excepted) 



6500 



6000 






4-» 

C 



c 
o 

■p 

> 

a) 



UMBREPTS - HARDWOODS ,## * 



••« 



,••' 



,••' 



,•• 



•••• 



••• 



7< 
? 

. SP0D0S0LS - SPRUCE - FIR 




Moisture Gradient 

Annual soil temperatures are shown by thin dashed lines 



207 



Figure 3. Soils patterns of the Great Smoky Mountains — 
Heath vegetation 



■p 

CD 
0) 



c 

cd 
S-. 
o 



cd 

c 
o 

cd 

> 

—i 



6500 



6000 



5500 



5000 



^500 



uooo 



3500 



3000 



2500 



2000 



1500 



, ' : 

:. 



SPODOSOLS OR HISTOSOLS 



9* 







• • 



• • 



• ••• 







,.••• 


















UDULTS 



••• 



15° •• 







.••* 



mesic 



xeric 



Moisture Gradient 

Annual soil temperatures are shown by thin dashed lines 



208 



SPODOSOLS 


INCEPTISOLS 
(MOR) 


INCEPTISOLS 
(MULL) 


INCEPTISOLS 
(MULL) 



•H 
I 

QJ 
O 

3 

D, 

00 



w 

O 
O 

3C 
c 

CD 

x: 

L 
O 



PARENT MATERIAL 
coarse 



medium 



STABLE TOPOGRAPHY AT 1700 m 

Figure A. Simplified vegetation-soil relationship 
for the Great Smoky Mountains 



209 



BIBLIOGRAPHY 

Beesley, T. E., et al. 1955. Soil survey of Cocke County, Tennessee. U.S. 

Government Printing Office, Washington, DC. 171 p. + maps. 
Bogucki, D. J. 1970. Debris slides and related flood damage with the 

September I, 1951, cloudburst in the Mt . LeConte-Sugar I and Mountain area, 

Great Smoky Mountains National Park. PhD. Dissert., Univ. of Tennessee, 

Knoxv i I I e . 
Coile, T. S. 1938. Podzol soils in the Southern Appalachian Mountains. Sci. 

Soc. Am. Proc. 3:274-279. 
Elder, J. A., et al. 1959. Soil Survey of Blount County, Tennessee. U.S. 

Government Printing Office. Washington, DC. 119 p. + maps. 
Golden, M. S. 1974. Forest vegegation and site relationships in the central 

portion of the Great Smoky Mountains National Park. Ph.D. Dissert., 

Univ. of Tennessee, Knoxville. 
Goldston, E. F., W. A. Davis, C. W. Croom, and W. J. Moran. 1954. Soil survey 

of Haywood County, North Carolina. U.S. Government Printing Office, 

Washington, DC. 112 p. + maps. 
Hall, W. G., B. W. Jackson, and T. R. Love. 1981. Soil survey of Monroe 

County, Tennessee. USDA Soil Conservation Service and Forest Service and 

Univ. of Tennessee Agric. Exp. Stn. 107 p. + maps. 
Hubbard, E. H., et al. 1956. Soil survey of Sevier County, Tennesse. U.S. 

Government Printing Office, Washington, DC. 134 p. 
King, P. B., R. B. Neuman , and J. B. Hadley. 1968. Geology of the Great Smoky 

Mountains National Park, Tennessee and North Carolina. U.S. Geolog. 

Survey Prof. Paper 587. 23 p. 
Knight, W. R. 1979. Relationship of soils and vegetation to topography and 

elevation in the Cumberland Mountains of Campbell County, Tennessee. M.S. 

Thesis. Univ. of Tennessee, Knoxville. 152 p. 
Losche, C. K., R. J. McCracken, and C. B. Davey. 1970. Soils of steeply 

sloping landscapes in the Southern Appalachian Mountains. Soil Sci. Soc. 

Am. Proc. 34:473-478. 
McCracken, R. J., R. E. Shanks, and E. C» Clebsch. 1952. Soil morphology and 

genesis at higher elevations of the Great Smoky Mountains. Soil Sci. Soc. 

Am. Proc. 26:384-388. 
McGinnis, J. T. 1958. Forest litter and humus types of East Tennessee. M.S. 

Thesis. Univ. of Tennessee, Knoxville. 82 p. 
Springer, M. E., H. R. DeSelm, and J. A. Elder. 1975. Soils-ecology tour in 

the Ridge and Valley and Great Smoky Mountains of East Tennessee and 

Western North Carolina. Sponsored by S-5 and S-7 of Soil Sci. Soc. Am. 

15 p. 
Springer, M. E., and J. A. Elder. 1980. Soils of Tennessee. Univ. of 

Tennessee Agric. Exp. Stn. Bull. 596. 66 p. + map. 
Vanderford, C. F. 1897. The soils of Tennessee. Univ. of Tennessee Agric. 

Exp. Stn. Bull. Vol. 10, No. 3. 139 p. 
Weaver, G. T. 1972. Dry matter and nutrient dynamics in red spruce-Fr aser 

fir and yellow birch ecosystems in the Balsam Mountains, Western North 

Carolina. Ph.D. Dissert. Univ. of Tennessee, Knoxville. 
Wolfe, J. A. 1967. Forest soil characteristics as related to vegetation and 

bedrock in the spurce-fir zone of the Great Smoky Mountains. Ph.D. 

Dissert. Univ. of Tennessee, Knoxville. 



210 



LEAD IN VEGETATION, FOREST FLOOR MATERIAL, AND SOILS 
OF THE SPRUCE-FIR ZONE, GSMNP 

Mary Anna Bogle and Ralph R. Turner!/ 

Abstract . --Based on a survey during 1982, lead concentrations 
in vegetation, litter and soils of the spruce-fir zone of the 
Great Smoky Mountains National Park are generally less than 
values reported for similar sites in the northeastern United States 
and western Europe. As expected, lead concentrations increased 
with increasing age of spruce and fir foliage, and with increasing 
degree of decomposition of litter. Fir bole wood was higher 
in lead than spruce bole wood, but both species were far below 
acutely phytotoxic levels. Although the results of this study 
indicated no immediate cause for concern, periodic monitoring of 
lead and other metals in the spruce-fir zone should be continued 
to provide early detection of significant changes. 

The biogeochemistry of lead in forest ecosystems continues to be of 
considerable interest. Among numerous metals studied, lead stands out 
in showing a very strong tendency to accumulate in the forest floor 
(Reiners et al . 1975; Heinrichs and Mayer 1980; Smith and Siccama 1981; 
Siccama et al. 1980; Andresen et al. 1982; Friedland et al. in press). 
This behavior is consistent with its strong affinity for organic matter and 
with its low solubility in forest soil even at low pH (Tyler 1978, 1981). 
High elevation sites, such as the spruce-fir zone of the Appalachians, 
although remote, are especially likely to show high concentrations of lead 
due to their unique orographic conditions; in general they exhibit hiqher 
concentrations in foliage and forest floor material than low elevation sites 
of the same region (Reiners et al . 1975; Wiersma and Brown 1980; Johnson et 
al. 1982). In fact, some lead values for forest floor material of montane 
forests approach values for urban areas and areas adjacent to roadways. The 
increased lead levels for high elevation sites (compared to lower elevation 
sites) have been attributed to four features of the sites: (1) increased 
precipitation due to orographic effects, (2) addition of cloud and fog 
interception, (3) higher wind speeds favoring higher impaction of small 
particles on surfaces of vegetation and higher diffusion rates of submicron 
particles across the boundary layer, and (4) predominance of coniferous 
foliage with higher leaf area indices and year-round persistence (Reiners 
et al . 1975; Lovett et al . 1982). This increases the likelihood that such 
high elevation sites, although remote from industrial sources, receive high 
exposure to certain pollutants. 



i/Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, 
Tennessee 37831. Research sponsored by the Department of Interior, National 
Park Service, NPS 0492-082-2 with the U.S. Department of Energy, under 
contract W-7405-eng-26 with Union Carbide Corporation. Publication No. 2277. 



By acceptance ol this article, the 
publisher or recipient acknowledges 
the U.S. Government's right to 
retain a nonexclusive, royalty tree 
license in and to any copyright 
covering the article 

211 



Prior to this study, published data on lead concentrations in the 
spruce-fir ecosystem of the Appalachians had been limited to work done 
primarily in the White and Green Mountains of New England and to the work of 
Wiersma and colleagues in the Great Smoky Mountains National Park (GSMNP). 
Wiersma et al. (1979) reported very high concentrations (378-879 yg/g; 
X=506 ug/g) of lead in the forest floor at one spruce-fir site in the 
GSMNP. These values are higher than any previously reported for montane 
ecosystems unimpacted by smelters or urban automobile traffic and raise 
questions concerning the magnitude of Pb contamination in the GSMNP and 
the possible adverse effect on the spruce-fir ecosystem. Lead is not only 
directly toxic to plants and animals but has also been implicated in reduced 
decomposition rates of forest floor material (Tyler 1972; Ruhling and Tyler 
1973; Jackson and Watson 1977), thus interfering with the cycling of 
essential nutrients in the forest ecosystem. Vogelmann (1983) has also 
suggested a synergistic effect between Pb and acid rain, resulting in the 
death or sharp decline in growth rate of spruce trees and other plants. 
The high natural resource value of the GSMNP is unquestioned, and thus it 
is imperative that any potential threat by a contaminant, such as lead, be 
detected early. Our study was conducted with the following objectives: 
( 1 ) to determine whether lead concentrations in the forest floor horizons of 
the spruce-fir zone of the GSMNP are comparable with reported values for 
forest floor material from other spruce-fir sites (e.g., in New England and 
West Germany), (2) to expand the data base for Pb for the spruce-fir zone by 
determining lead concentrations in foliage and bole wood of spruce and fir, 
in forest floor subunits (Oi, Oe, and Oa horizons), and in soil subunits 
(A and B horizons), (3) to determine if there is evidence of root or foliar 
absorption of Pb in vegetation, (4) to determine if Pb concentration in the 
forest floor increases with increasing degree of decomposition, as expected, 
and (5) to determine if there is evidence of appreciable movement of Pb from 
organic to mineral horizons. Complete results of our study, including data 
for two hardwood sites, are given in Turner et al. (in press). 

MATERIALS AND METHODS 

Study Sites 

Five high elevation (>1700 m), spruce-fir sites were sampled between 
August and November 1982. Site descriptions are as follows: 

(1) Double Springs Gap--35°33' 50" N Lat, 83°30'06" W Long; 1740 m 

elevation; located 0.75 km east of the Double Springs Gap shelter and 
approximately 50 m south of Appalachian Trail on a gentle south-facing 
slope; forest canopy is dominated by red spruce ( Picea rubens Sargent) 
and Fraser fir ( Abies fraseri Poiret) with scattered yellow birch 
( Betula al legheniensis Britton), mountain ash ( Sorbus americana 
Marshall) and mountain maple ( Acer spicatum Lam. ) ; shrub layer 
consists of blackberry ( Rubus spp. ), witch hobble ( Viburnum alnifolium 
Marshall), and wood fern ( Dryopteris campyloptera ClarksonJ. 



212 



(2) Clingmans Dome Road — 35°33'32" N Lat, 83°30'38" W Long; 1900 m 
elevation; located 0.2 km north of entrance to parking lot and 
approximately 50 m east of Clingmans Dome Rd on a steep east-facing 
slope; forest canopy is dominated by red spruce with scattered yellow 
birch and Fraser fir; shrub layer consists of blackberry, witch hobble, 
and wood fern. Site was chosen because of its relative proximity to a 
heavily travelled road. 

(3) Mt. Collins— 35°35'35" N Lat, 83°28'25" W Long; 1790 m elevation; 
located 50 m west (uphill) from spring on trail west of Mt. Collins 
shelter on a gentle north-facing slope; forest canopy is dominated by 
red spruce with scattered yellow birch and Fraser fir; shrub layer 
consists of blackberry, witch hobble, and wood fern. Forest floor 
material from this Mt. Collins site was previously reported (Wiersma 
et al . 1979) to have elevated levels of Pb. 

(4) Mt. LeConte, West Peak— 35°39' 18" N Lat, 83°27'05" W Long; 1920 m 
elevation; located approximately 1 km west of LeConte Lodge along 
the crest of an east-west trending ridge; red spruce and Fraser fir 
are canopy dominant with scattered mountain ash, pin cherry ( Prunus 
pensylvanica L. ) and yellow birch; blackberry, witch hobble, and wood 
fern constitute the main shrub layer species. 

(5) Mt. Kephart— 35°37'50" N Lat, 83 23'25" W Long; 1880 m elevation; 
located near the crest of Mt. Kephart on a moderately steep southwest 
slope near the junction of the Appalachian Trail with the Boulevard 
Trail; red spruce is canopy dominant with scattered Fraser fir, yellow 
birch, and mountain ash; dead and/or fallen Fraser fir have left large 
openings in the canopy; blackberry, wood fern, and witch hobble 
comprise the shrub layer. 

Sample Collection and Preparation 

Because this was largely an exploratory study, samples were of the 
"grab" type, with many being composites of several grab samples. In 
contrast to earlier studies conducted in the GSMNP, more effort was made 
to reduce variability among replicates by dividing samples into more 
homogeneous subunits. 

One of two sampling patterns was followed at each site, depending on 
site topography. A linear pattern of replicates taken at 5-10 m intervals 
was used at steep sites including Clingmans Dome Road (parallel to road), 
Mt. LeConte, and Mt. Kephart. A circular pattern with replicates taken at 
equal intervals around a 15-m-radius circle was used at flatter sites, 
i.e., Double Springs Gap and Mt. Collins. Table 1 gives an inventory of 
the samples collected at each site and the number of replicates. In all 
cases samples were handled using polyethylene gloves and double-bagged in 
polyethylene collection bags. During sample preparation, extreme care 
was taken by the use of a laminar-flow clean bench to prevent possible 
contamination of samples or cross-contamination between samples. All 
processed samples were stored in acid-cleaned bottles. 



213 



Table 1 .- -Inventory of sample types and number of replicates at each site in the GSMNP. 



Numbers 


in ( ) unde 


r bole cores are the number of cores ana 


lyzed. 






Double 


Clingmans 






Sample type Sp 


rings Gap 


Dome Mt. Collins Mt. Le Conte 


Mt. Kephart 


Total 


Soil 










A 


5 


3 5 6 


5 


24 


B 


5 


3 5 6 


5 


24 


Roots 










Red spruce 


5 






5 


Fraser fir 


5 






5 


Yellow birch 


5 






5 


Forest floor 










Oi (Litter) 


5 


3 5 7 


5 


25 


Oe (Fermentation) 


5 


3 5 5 


5 


23 


Oa (Humus) 


5 


3 5 5 


5 


23 


Foliage 










Red spruce Old 


5 


5 


2 


12 


Current 


5 


5 


2 


12 


Fraser fir Old 


3 


5 


2 


10 


Current 


3 


5 


2 


10 


Yel low birch 


2 






2 


Bole cores 










Red spruce 


5(5) 


5(1) 


4(1) 


14(7) 


Fraser fir 


3(3) 


5(1) 


2(1) 


10(5) 


Yellow birch 


2(2) 






2(2) 



Branches of red spruce and Fraser fir foliage were collected with a 
pole pruner from near the top of canopy-dominant trees or from solitary 
trees growing in exposed areas (i.e., ridge crests). Deciduous foliage 
of yellow birch was collected from lower branches of trees at one site, 
Double Springs Gap. Unwashed foliage from spruce and fir was separated in 
the laboratory into "old" (i.e., 2- to 4-year-old and "current" (i.e., J 982 
growth) needles before oven drying at 75° to 100°C. Dried needles were 
then removed from their stems and stored. Unwashed yellow birch leaves were 
also oven dried and broken into small fragments before storage. All foliage 
samples were put into solution by nitric-perchloric acid digestion without 
further processing (Jackson 1964). 

Xylem cores were taken with a 46-cm steel (Ni-plated) increment corer 
with a 12-mm I.D. After removal of the outer 1-2 mm of wood with a stainless 
steel scalpel, each core was cut into sections. Core sections were dried to 
a constant weight at 95°C, dry ashed (450°C) in 25-ml beakers, and dissolved 
in IN HN0 3 (Baker 'Ultrex') and 100 ul of 30% H 2 2 . 



214 



Roots were collected at only one site, Double Springs Gap, by uprooting 
saplings of red spruce and Fraser fir or by excavating at the base of 
large yellow birches. A sample consisted of root segments ranging up to 
approximately 1 cm in diameter. Roots were cleaned with distilled water 
while in the original collection bags using an ultrasonic cleaner. Water 
was changed repeatedly until it remained clear upon sonification of the 
sample. Roots (oven dried at 100°C) were put into solution by dry ashing 
(450°) followed by dissolution in IN HN0 3 ('Ultrex') and 30% H 2 02- 

Forest floor samples were obtained by sequential removal and separation 
of the Oi, Oe, and 0a layers (Soil Conservation Service, 1981) using a 
stainless steel spatula or trowel. Individual samples were assembled by 
compositing material from several locations within an -20 rrr area. 
The criteria for separation of these layers correspond to those used in many 
previous studies of forest floor material, but as recently noted by Federer 
(1982) the actual separation is somewhat subjective. In the laboratory, 
samples were oven dried at 75° to 100°C and then ground in a Wiley mill with 
stainless steel grinding components. Loss-on-ignition (LOI) values were 
determined on all forest floor material in this study as a convenient way of 
comparing consistency of sampling a horizon within a site and between sites 
and to permit assessment of Pb concentrations on an organic matter (ash-free) 
basis. Ashed (450°C) samples were dissolved in IN HNO3 and 30% H 2 2 . 

Mineral soil samples were obtained by coring or excavation and 
separated qualitatively into A and B horizons in accordance with the 
standard definitions of these horizons (field classification based on 
stratigraphic position, color, and texture). After drying at 75° to 100°C, 
samples were finely crushed using a mortar and pestle, sieved through a 
stainless steel U.S. Standard Sieve No. 18 (1.00 mm), and digested in a 
1:1 mixture of concentrated HNO3 and HC1 using the procedure described 
by Anderson et al . (1974). 

All lead analyses were performed with either flame (AA) or graphite 
furnace (FAA) atomic absorption spectrophotometry on solutions prepared 
by wet oxidation or by dry ashing and dissolution in acid. Instrument 
calibration was by the method of standard additions for FAA and by standard 
curve for AA. 

Qual ity Assurance 

Since the reliability of much of the extant data on lead in the 
environment has been seriously questioned (NAS 1980), the quality of the 
analytical data generated in this study was monitored in several ways to 
assess and improve precision and accuracy of results. The centralized 
analytical facility at ORNL, which performed all atomic absorption analyses, 
maintains its own Quality Assurance program. In addition, the measures 
listed below were taken to assure the reliability of our data. 



215 



(1) Use of Standard Reference Material (SRM)--At least one sample of SRM 
having a similar matrix and lead concentration as the sample was run 
with every batch of 10 to 25 samples. SRMs run included NBS 1571 
(orchard leaves), NBS 1573 (tomato leaves), NBS 1575 (pine needles), 
NBS 1645 (river sediment), CCMET S0-2 ('B' soil), and CCMET SO-4 ('A' 
soil). The latter soil SRMs were obtained from the Canadian Centre for 
Mineral and Energy Technology. 

(2) Replicates—Selected samples were digested and analyzed in duplicate or 
triplicate to assess procedural precision. With one exception, 
coefficients of variation for replicates were <±10% and frequently <±5% 

(3) Reanalysis of Selected Samples — As an indication of day-to-day 
variability, a few samples were reanalyzed with later batches of 
samples. Initial and subsequent values agreed within ±10%. 

(4) Cross Method Check of Analysis—Digestion of samples by independent 
methods (wet oxidation or dry ashing) was done to reveal problems with 
sample digestion. Values for forest floor samples prepared both ways 
agreed within ±10%, and the more convenient method, i.e. dry ashing, 
was used. Trial runs with foliage indicated potential low recovery of 
Pb when dry ashing was used. Although the addition of 100 yl of 30% 
HoO? to foliage ash resulted in good recovery of Pb, it was decided 
that all foliage samples would be run by wet oxidation to avoid 
uncertainty. 

(5) Spike Recovery — All analyses performed by FAA entailed sample spiking 
as part of the calibration procedure. Selected samples (-10%) run by 
AA were also spiked. Spiking allowed for differences in sample 
matrices, which may cause suppression or enhancement, to be taken 
into account. 

(5) Use of Field Sites in Common with Earlier Studies — Among the five 
spruce-fir sites selected for sampling, two (Mt. Collins and Double 
Springs Gap) were chosen because earlier studies of Pb in litter had 
been conducted at these sites by Wiersma et al . (1979) and Breckenridge 
and Wiersma (1982). 

RESULTS AND DISCUSSION 

Vegetation 

Foliage samples were not washed and thus analytical results for foliage 
reflect the sum of internal tissue levels and surface contamination. 
Concentrations of Pb in red spruce, Fraser fir, and yellow birch generally 
follow the relationship: roots > foliage > bole. This pattern 
is consistent with other published data (Van Hook et al. 1977; Nilsson 1972; 
Heinrichs and Mayer 1980; Smith and Siccama 1981). Lead concentrations in 
foliage, averaged by site and for all sites, for the three species sampled 
are given in Table 2. Average concentrations range from 0.38 ug/g dry 
weight (D.W.) for current foliage of Fraser fir collected at Double Springs 
Gap to a high of 4.1 ug/g D.W. for old needles of Fraser fir collected at 
the same site. This range of concentrations for Fraser fir is consistent 



216 



Table 2. -- Average concentrations (pg/g dry wt) of lead in foliage from 



the 


spruce-fir zone of 


GSMNP. Values in 


( ) are S.D. (or 


range 






if N = 2). X 


= average for all 


three sites. 








Double Springs 


Mt. Le Conte 


Mt. Kephart 


X 


Red spruce 
Current 




0.69 a ' x 
(0.18) 


0.62 a ' x 
(0.24) 


0.61 a,x 
(0.60-0.61) 


0.65 x 
(0.18) 


Old 




0.66 a ' x 
(0.26) 


1.03 a ' b ' x 
(0.33) 


1.45 b ' x 
(1.1-1.8) 


0.95^ 
(0.42) 


Fraser fir 












Current 




0.38 a ' x 
(0.05) 


0.81 a ' x 
(0.61) 


0.61 a ' x 
(0.49-0.73) 


0.64 x 
(0.46) 


Old 




4.1 a>x 
(3.6) 


T.ga.y 
(0.61) 


2.6 a ' y 
(2.6-2.6) 


2.6^ 
(2.02) 


Yel low birc 


h 


2.4 
(2.2-2.6) 






2.4 



*For a given row averages followed by the same letter (a,b) are not 
significantly different at the 5% level (Walker-Duncan K-ratio or Student's 
t-test). For a given column and species, old and current averages followed 
by the same letter (x,y) are not significantly different at the 5% level 
(Student's t-test). 

with values reported by Wiersma and Brown (1980) for Fraser fir foliage 
collected in GSMNP in 1978. However, lead concentrations in needles of 
red spruce in our study are three to four times lower (see Table 3) than 
concentrations reported by Johnson and Siccama (1983) for red spruce from 
the boreal forest of Camels Hump, Vermont and almost eight times lower than 
red spruce needles collected in the Hubbard Brook Experimental Forest 
located in central New Hampshire (Smith and Siccama 1981). 

Intersite comparisons of coniferous foliage were made using the 
Duncan-Waller k-ratio t-test or Student's t-test (see Table 2). As might 
be expected due to similar orographic conditions at all five spruce-fir 
sites, no between-site differences in the lead concentrations of Fraser fir 
or current red spruce needles are observed. However, there is a significant 
difference in Pb concentration of old red spruce needles from Double Springs 
Gap and Mt. Kephart. This apparent difference may be an artifact of the lo 
number of replicate samples (N=2) at the Mt. Kephart site. 



w 



A comparison (Table 2) of average Pb concentrations in old needles with 
current needles reveals that, with one exception, old needles are higher 
in Pb. Although the difference is not always significant on a site-by-site 



217 



Table 3.- -A comparison of spruce-fir foliage and forest floor Pb concentrations 
(u_g/g dry wt.) from selected studies . 



Locality 



Foliage 



New 



Old 



Forest Floor 



Oi 



Oe 



Oa 



Reference 



GSMNP 



Spruce 


0.65 0.95 


52 


130 


Fir 


0.64 2.69 






Fir 


0.2-3.1 


- 


--?i n 




_ _ 


59.3 


132 



Green Mountains , 






Vermont 


Spruce 


~3 


(Camels Hump) 




- 


Vermont 




- 


White Mountains, 






New Hampshire 


Fir 


- 




Spruce-fir 


- 


Hubbard Brook , 






New Hampshire 


Fir 


7.4 




Spruce 


13.8 


Soiling Forest , 






West Germany 


Spruce 


5.4 12.0 


Skane, Sweden 


Spruce 


2.1 3.7 



225 266 
188- 

246 202 

110 114 

193- 



132 This study 

Wiersma and Brown 1980 
Breckenridge and Wiersma 198? 
Wiersma, personal communication 

Johnson and Siccama 1983 
175 Friedland et al., in press 

Johnson et al . 1982 

82 Reiners et al. 1975 
60 Reiners et al. 1975 

Smith and Siccama 1981 
Smith and Siccama 1981 



300 450 465 Heinrichs and Mayer 1980 
46 71 86 Nilsson 1972 



basis, it is significant when comparing averages for all sites. Numerous 
researchers, including Nilsson (1972) and Heinrichs and Mayer (1980), have 
reported similar results for old and new needles of coniferous trees 
(Table 3). These findings are reasonable considering the longer exposure 
time of old needles to surface deposition and to possible uptake of lead. 

Average Pb concentration in foliage of yellow birch is 2.4 ug/g D.W. 
This concentration in deciduous leaves seems high when compared to 
1-year-old needles of Fraser fir and red spruce but is consistent with 
the reputation of birch ( Betula spp.) as an accumulator of Pb (Cannon 1976; 
Smith and Siccama 1981). 

Bole wood Pb values for red spruce and Fraser fir are low, averaging 
0.03 ug/g D.W. and 0.25 ug/g D.W., respectively. An interspecific 
comparison of average lead concentrations in foliage and in bole wood 
lends some insight into the possible site of lead accumulation, i.e., 
whether the lead represents surface-deposited lead and/or tissue-incorporated 
lead. Fraser fir and red spruce Pb concentrations for current needles 
(0.64 ± 0.46 ug/g and 0.65 ± 0.18 yg/g D.W., respectively) are not 



218 



significantly different (P > 0.05). However, the average value of old 
Fraser fir needles (2.69 ± 2.02 g/g D.W.) is significantly higher (P<0.01) 
than that of old red spruce needles (0.95 ± 0.41 u g/g D.W.). This 
observation, combined with the fact that Fraser fir bole wood values are 
approximately ten times that of red spruce bole wood, suggests that more lead 
is incorporated by Fraser fir into foliage and bole tissue through root 
and/or foliar uptake than by red spruce; i.e., Fraser fir is an 'accumulator' 

Consistent with birch's reputation as an 'accumulator' of Pb are bole 
wood values averaging 5.1 ug/g D.W. and root concentrations as high as 
91 ug/g D.W. (X=51 ug/g D.W.), contrasted with an average concentration 
in roots of both red spruce and Fraser fir of 30 ug/g D.W. 

Forest Floor 

The average concentrations of lead in the Oi, Oe, and Oa horizons of 
the forest floor are 52, 128, and 132 ug/g D.W. respectively, with the 
composite average of the three layers being 105 pg/g D.W. (126 pg/g 
ash-free weight). These concentrations are difficult to compare with 
earlier results from spruce-fir sites in GSMNP (Wiersma et al. 1979; 
Breckenridge and Wiersma 1982) because of differences in sampling methods 
(e.g., forest floor material was not separated into subunits in the earlier 
two studies) and in sampling sites. However, a comparison of our results 
for average Pb concentrations at two sites in common with the earlier 
studies (summarized in Table 4) demonstrates that our values are lower at 
both sites for all forest floor horizons. More recent data from Wiersma 
(personal communication) for Double Springs Gap are consistent with our 
findings. The yery high Pb values reported earlier for Mt. Collins material 
suggest a contamination or analytical problem. In general, our Pb data for 
forest floor material are also less than recent published values for 
spruce-fir sites in the northeast (Table 3). Because of the measures we 
took to assure 'good' data during analysis of our samples (see Qua! ity 
Assurance section) as well as the recent communication of comparable 
values from Wiersma, we feel confident of our values. 

Table 4. - -Comparison of forest floor Pb values at two spruce-fir sites, GSMNP . 



Double Springs Gap 
Breckenridge and 
This study Wiersma 1982 Wiersma' 



Mt. Collins 



This study Wiersma et al . 1979 



Forest floor, Oi 69±16(5) 

Oe 125±20(5) 

Oa 125±34(5) 

X 106 



210±66(9) b 



59.3(10) 
132.0(10) 



47±8(5) 
120134(5] 
105±40(5) 

91 



506±155(9) b 



a Personal communication, 1983. 
Unincorporated litter - Oi and Oe horizons. 



219 



Intrasite comparisons of forest floor horizons reveal a nearly 
consistent trend toward increasing Pb concentration in forest floor horizons 
with increasing degree of decomposition. This trend is especially striking 
if ash-free concentrations for the three forest floor horizons are compared. 
With the exception of the Clingmans Dome Road site (where Oe == Oa), 
average Pb concentrations are significantly different at all sites for all 
three horizons with 0i<<0e<0a (Fig. 1). Reiners et al . (1975) in their 
study on trace metals in forest floor material conducted on Mt. Moosilauke, 
New Hampshire reported the opposite trend, decreasing Pb concentrations in 
forest floor layers with increasing degree of decomposition, and suggested 
that this finding indicated that the rate of dissemination of Pb aerosols 
was accelerating during the time of their study (early 70's). Several 
recent papers (e.g., U.S. EPA, 1983; Smith and Siccama 1981; Lindberg and 
Turner 1983; Turner et al. submitted) suggest that the rate of input of 
anthropogenic Pb into the atmosphere, and hence deposition of atmospheric 
Pb to the earth, has decreased over the last few years. Reconstructing 
historical trends in metal loadings from forest floor profiles is 
complicated, if not impossible, at present (see e.g. Friedland et al., 
in press). Nonetheless, our data do not seem to contradict the idea that 
atmospheric inputs of Pb to the GSMNP have been decreasing over the last 
few years . 



ORNL DWG 83 I9S'j 



* 200- 



I 



-£> 150- 




poub\. Spr C^c^g^ans 



U\ Coffin* M< L eCon»« ^ Kephar 
SITE 



Legend 

E2 LITTER 

■I FERMENTATION 

ea humus 



Figure l.--Lead concentration (ash-free basis) in forest floor horizons of 
five spruce-fir sites (GSMNP). 



220 



McGinnis (1958) determined the standing pool of forest floor material 
from a spruce-fir site near Newfound Gap (GSMNP) to be 844, 2496, and 
12702 kg/hectare for the Oi, Oe, and Oa horizons, respectively. Using these 
values and our values for Pb concentrations in the forest floor layers, a 
very rough estimate of 0.20g/m^ can be calculated for the total Pb content 
of the spruce-fir forest floor. It should be cautioned that this estimate 
may well be low because other researchers, including Reiners et al. (1975), 
have found forest floor biomass to be considerably higher than that reported 
by McGinnis. 

Soi Is 

Average concentrations of Pb in soil horizons (A=33 ug/g D.W. and 
B=24 yg/g D.W.) are similar to values reported by others for soils of the 
GSMNP (Boergen and Shacklette 1981; Wiersma et al. 1979) and are typical 
for soils developed on low-grade metamorphic bedrock, suggesting little 
appreciable movement of Pb into the soil. Our values for pH of A horizon 
soils range from 3.2 to 3.5, for B horizon soils from 3.3 to 3.7. These 
values agree well with data presented by McGinnis (1958) for soils of a 
spruce-fir site in the Smokies. Even at low pH, Tyler (1978) found Pb to be 
so tightly bound to organic material that it was essentially immobile except 
under conditions favoring the leaching of organic matter (Tyler 1981). As 
expected based on their higher content of organic matter and the affinity of 
Pb for organic matter, A horizon soils are higher in Pb than B horizon. 
The difference is significant (P < 0.05) at the Double Springs Gap, 
Mt. Collins, and Mt. LeConte sites. 

CONCLUSIONS 

The results of our study suggest that Pb concentrations are not 
exceptionally high in the spruce-fir zone of the GSMNP and in general 
are less than values reported for similar sites in the northeastern 
United States and western Europe. We suspect that our results are lower 
than the previously reported high values for Mt. Collins' forest floor 
material due to possible contamination or analytical problems in the earlier 
study and not because of differences in sampling methodology nor because Pb 
concentrations have declined greatly since 1978. 

Comparison of our data with available data on acute toxicity of Pb to 
higher plants (almost exclusively agricultural species) suggests that Pb 
concentrations in the GSMNP are well below the level where such effects are 
noticeable. However, information on Pb toxicity to forest trees is virtually 
lacking. Likewise, even for agricultural species, information on the subtler 
effects of Pb either alone or in combination with other contaminants, is 
scarce; thus it would be premature to conclude that current Pb levels in the 
spruce-fir zone pose no ecological threat. If studies at spruce-fir sites 
in the northeastern United States and in western Europe, where Pb deposition 
and concentrations are higher, validly implicate heavy metals in the forest 
declines in these areas, then Pb and other metals in the GSMNP should 
continue to be closely monitored. Recent data from a variety of sources, 
including this study, suggest that air concentrations and deposition of 



221 



Pb are decreasing primarily in response to reduced emissions from vehicles. 
While these emission reductions stem from regulations aimed at protecting 
catalytic exhaust systems and human health, in the long term they will 
likely also be beneficial to fragile high elevation ecosystems, such as the 
spruce-fir zone of the GSMNP. 

LITERATURE CITED 

Anderson, J. 1974. A study of the digestion of sediment by the 
HNO3-H2SO4 and the HNO3-HCI procedures. Atomic Absorption 
Newsletter 13:31-32. 

Andresen, A. M., A. H. Johnson, and T. G. Siccama. 1980. Levels of lead, 
copper and zinc in the forest floor in the northeastern United States. 
J. Environ. Qual. 9:293-296. 

Boergen, J. G. and H. T. Shacklette. 1981. Chemical analyses of soils 
and other surficial materials of the conterminous United States. 
U.S. Geol. Survey Open-File Rpt. 81-197, 142 pp. 

Breckenridge, R. P. and G. B. Wiersma. 1982. Preliminary evaluation 

of trace elements in samples from the Great Smoky Mountains Biosphere 
Reserve. Eighth Annual Scientific Research Meeting, Upland Areas of 
the Southeast Region NPS, GSMNP, Townsend, Tennessee, June 1982. 10 pp 

Cannon, H. L. 1976. Lead in vegetation [in] Lead in the Environment. 
U.S. Geol. Survey Prof. Paper 957, p. 53-72. 

Federer, C. A. 1982. Subjectivity in the separation of organic horizons of 
the forest floor. Soil Sci. Soc. Am. J. 46:1090-1093. 

Friedland, A. J., A. H. Johnson, and T. G. Siccama. Trace metal content of 
the forest floor in the Green Mountains of Vermont: spatial and 
temporal patterns. Water, Air, and Soil Pollution (in press). 

Friedland, A. J., A. H. Johnson, T. G. Siccama. Trace metal distributions 
in forest floor profiles: comparisons from three localities in New 
England. Soil Sci. Soc. Am. J. (in press). 

Heinrichs, H. and R. Mayer. 1980. The role of forest vegetation in the 
biogeochemical cycle of heavy metals. J. Environ. Qual. 9:111-118. 

Jackson, D. R. and A. P. Watson. 1977. Disruption of nutrient pools and 
transport of heavy metals in a forested watershed near a lead smelter. 
J. Environ. Qual. 6:331-338. 

Jackson, M. L. 1964. Soil chemical analysis. Prentice-Hall, Inc., 
New Jersey. 

Johnson, A. H., T. G. Siccama, and A. J. Friedland. 1982. Spatial and 
temporal patterns of lead accumulation in the forest floor in the 
northeastern United States. J. Environ. Qual. 11:577-580. 



222 



Johnson, A. H. and T. G. Siccama. 1983. Spruce decline in the northern 
Appalachians: evaluating acid deposition as a possible cause. 
Proceedings of the TAPPI : 301-310. 

Lindberg, S. E. and R. R. Turner. 1983. Trace metals in rain at forested 
sites in the eastern United States. [In] Heavy Metals in the 
Environment, Vol. 1, CEP Consultants Ltd: Edinburg, U.K. pp. 107-114. 

Lovett, G. M., W. A. Reiners, and R. K. Olson. 1982. Cloud droplet 

deposition in subalpine balsam fir forests: hydrological and chemical 
inputs. Science 218:1303-1304. 

McGinnis, J. T. 1958. Forest litter and humus of east Tennessee. 
(M.S. Thesis, University of Tennessee). 82 pp. 

National Academy of Sciences (NAS), Committee on Lead in the Human 

Environment. 1980. Lead in the human environment. Washington, D.C.: 
National Academy of Sciences. 

Nilsson, I. 1972. Accumulation of metals in spruce needles and needle 
litter. Oikos 23:132-136. 

Reiners, W. A., R. H. Marks, and P. M. Vitousek. 1975. Heavy metals in 
subalpine and alpine soils of New Hampshire. Oikos 26:264-275. 

Ruhling, A., and G. Tyler. 1973. Heavy metal pollution and decomposition 
of spruce needle litter. Oikos 24: 402-416. 

Siccama, T. G., W. H. Smith, and D. L. Mader. 1980. Changes in lead, zinc, 
copper, dry weight, and organic matter content of the forest floor of 
white pine stands in central Massachusetts over 16 years. Environ. 
Sci . Technol . 14: 54-56. 

Smith, W. H. and T. G. Siccama. 1981. The Hubbard Brook Ecosystem Study: 
biogeochemistry of lead in the northern hardwood forest. J. Environ. 
Qual. 10:323-333. 

Soil Conservation Service. 1981. Examination and description of soils in 
the field. Chapter 4 (revised). Soil Survey Manual. S.C.S. Directive 
430-V. 

Turner, R. R., M. A. Bogle, and C. F. Baes III. In press. Survey of 

lead in vegetation, forest floor, and soils of the Great Smoky Mountain 
National Park. National Park Service Report, Denver, Colorado. 

Turner, R. S., A. H. Johnson, and D. Wang. Biogeochemistry of lead in 

McDonalds Branch watershed, New Jersey Pine Barrens. J. Environ. Qual. 
(submitted) . 

Tyler, G. 1972. Heavy metals pollute nature, may reduce productivity. 
Ambio 1: 52-59. 



223 



Tyler, G. 1978. Leaching rates of heavy metal ions in forest soil. Water, 
Air, and Soil Pollution 9: 137-148. 

Tyler, G. 1981. Leaching of metals from the A-horizon of a spruce forest 
soil. Water, Air, and Soil Pollution 15: 353-369. 

U.S. Environmental Protection Agency. 1983. National air quality and 
emission trends report, 1981. Research Triangle Park, N.C.: 
U.S. Environmental Protection Agency, Office of Air Quality Planning 
and Standards; Publication No. EPA-450/4-83-01 1. 

Van Hook, R. I., W. F. Harris, and G. S. Henderson. 1977. Cadmium, lead, 
and zinc distributions and cycling in a mixed deciduous forest. Ambio 
6: 281-286. 

Vogelmann, H. W. 1982. Catastrophe on Camels Hump. Natural History 
91: 8-14. 

Wiersma, G. B., R. Hermann, K. W. Brown, C. Taylor, and J. Pope. 1979. 

Great Smoky Mountains preliminary study for biosphere reserve pollutant 
monitoring. EPA-600/4-79-072. U.S. Environmental Protection Agency 
Report, Las Vegas, Nevada, 56 pp. 

Wiersma, G. B., and K. W. Brown. 1980. Background levels of trace elements 
in forest ecosystems. Symposium on Effects of Air Pollutants on 
Mediterranean and Temperate Forest Ecosystems, Riverside, California, 
22-27 June 1980, 7 pp. 



224 



POLLUTANT DEPOSITION IN MOUNTAINOUS TERRAIN 
Gary M. Lovett 

Abstract . Theoretical considerations suggest that the high 
elevation forests in mountainous areas receive substantially more 
atmospheric deposition than do the forests of the surrounding 
lowlands. Wet deposition should increase with elevation because 
of orographic enhancement of precipitation and increased deposition 
of snow, which may be more polluted than rain. Dry deposition 
should be greater in high-elevation forests because of greater 
wind speeds, higher relative humidities, greater surface area 
of vegetation present during the entire year, and greater filtering 
efficiency of needles compared to broad leaves. Somewhat lower 
concentrations of airborne particles and gases at remote high 
elevation sites may act to diminish the elevational increase of 
dry deposition to some extent. In addition to increased wet and 
dry deposition, cloud water deposition is likely to be significant 
at high elevations because of the frequent presence of wind-driven 
clouds. At low elevations, clouds and fogs are probably negligible 
as a deposition vector because they occur less frequently and are 
usually associated with still air. 

Experimental verification of these expected trends is not easily 
found, but studies on cloud water deposition and lead accumulation 
suggest their accuracy. Additional data on air quality, meteorology, 
and precipitation chemistry are needed for high elevations before 
atmospheric deposition of any airborne substance can be determined 
with certainty. 

INTRODUCTION 

Several networks now exist for measuring pollutant deposition in rain and snow 
(called wet deposition) across the North American continent (EPA 1983). 
Although no similar network is yet operative for deposition of atmospheric 
particles and gases (dry deposition), such a network is being developed. 
The distances between monitoring stations in these networks is necessarily 
large, usually on the order of hundred of kilometers or more. Observational 
evidence suggests that the presence of mountain ranges can effect dramatic 
changes in deposition over spatial scales on the order of tens of kilometers, 
which is below the spatial resolution of the national monitoring networks. 
Very few studies have focused on elevational patterns of deposition, therefore 
few data are available to document the effect. This paper summarizes the 
factors that control wet and dry deposition, shows how those factors might 
change along an elevational gradient, and discusses some North American data 
that illustrate topographical effects on deposition. Data from the southern 
Appalachians are emphasized where possible. 



1. Environmental Sciences Division, Oak Ridge National Laboratory, Oak 
Ridge, Tennessee 37831 

225 



WET DEPOSITION 

Two processes control the rate of wet deposition of pollutants: the 
scavenging of the pollutant material by atmospheric liquid water and ice, 
and the delivery of the incorporated pollutants to the ground by precipitation 
The latter process certainly changes with elevation; orographic enhancement 
of precipitation is a well-known phenomenon. Dingman (1979) calculated that 
precipitation increases 0.075 cm/y for every meter of elevational gain in 
the mountains of New Hampshire and Vermont. On the west slope of the Great 
Smoky Mountains, Shanks (1954) found a precipitation increase of over 50 
percent in the elevational range from 445 to 1523 m. The rate of increase 
was 0.076 cm/y per meter elevation, remarkably close to the New England value. 
Shanks found that the rate of precipitation enhancement decreased in the 1520 
to 1920-m range, but attributed this change to a different exposure of the 
highest station. 

These increases in precipitation with elevation do not necessarily imply 
proportional increases in wet deposition of pollutants. Wet deposition of 
SO, and trace metals has been found to be positively, but nonlinearly, 
related to precipitation amount (Hicks and Shannon 1979, Lindberg 1982), 
presumably because the ef feciency of precipitation scavenging processes 
decreases as the air is cleaned by precipitation. Therefore, elevational 
enhancement of precipitation should bring a disproportionately smaller 
enhancement of wet deposition. 

Precipitation scavenging processes can alter this elevational effect in 
other ways as well. For example, if the pollutants are released at low 
elevations, they may not be dispersed to altitudes high enough to affect 
the precipitation high in mountainous areas. The height over which 
pollutants are thoroughly mixed varies substantially with geographic area 
and weather conditions (EPA 1983) . Lack of thorough vertical mixing would 
imply cleaner air, and thus cleaner rain, at high elevations, and this could 
counteract the effect of an increased amount of precipitation. The Tennessee 
Valley Authority (1983) collected wet deposition at 1016, 1367, and 1822 m in 
Raven Fork Watershed in the Great Smoky Mountains, and the data showed no 
significant effect of elevation on concentrations of SO^ - , NO3 - , and H+ 
ion rain (analysis of variance, p >0.05). These data were collected over 
only one growing season, however, and a longer-term record with more sites 
would be needed to prove conclusively that rain chemistry does not vary 
with elevation. 

Compared to low elevations, a greater percentage of the precipitation at 
high elevations is delivered as snowfall. This can affect the total wet 
deposition because snow is generally considered to be more efficient than 
rain at scavenging particles and gases from the air (Raynor and Hayes 1983, 
Knutson and Stockham 1977). This would result in higher annual average 
concentrations of pollutants in precipitation at higher elevations. 

Thus, competing trends govern the change in wet deposition with elevation: 
increased amounts of precipitation and greater percentages of snowfall tend 



226 



to cause an increase in wet deposition, while cleaner air at high elevations 
could cause a decrease. The relative importance of these processes probably 
varies between mountain systems, and should be determined experimentally. 
For the southern Appalachians, however, one might expect a moderate increase 
in wet deposition with elevation because, based on the limited TVA data 
(TVA 1983), rain chemistry does not appear to change significantly with 
elevation . 

DRY DEPOSITION 

Dry deposition of particulate and gaseous pollutants to vegetated surfaces 
is controlled by a large number of factors including air quality, wind speed, 
morphological characteristics of the vegetation, and relative humidity 
(Sehmel 1980, Hosker and Lindberg 1982). Many of the controlling factors, 
especially those listed above, can change with elevation; thus the rate of 
dry deposition may also change with elevation. 

Air quality may improve with elevation, but conclusive data to support 
this are lacking. Skelly et al. (1983) and Duchelle et al. (1982) report 
SO2 and O3 measurements in the mountains of western Virginia, and Davidson 
et al. (in press) report atmospheric concentrations of trace elements on 
Clingman's Dome in the Great Smoky Mountains National Park. However, none 
of these high-elevation data sets is accompanied by a simultaneously measured 
low-elevation 'data set, so direct elevational comparisons are not possible. 
Davidson et al. note that the trace metal concentrations at Clingman's Dome 
are less than those measured by Stevens et al. (1980) at a lowlands site 
13 km away, but suggest that the differences may be the result of sampling 
methodology and proximity of the lower site to pollutant sources — in this 
case roads and populated areas. This emphasizes that in many cases it may 
be difficult to distinguish between the effects of elevation and remoteness 
in controlling air quality in mountainous areas that are frequently distant 
from pollution sources. 

Wind speeds generally increase with elevation. Near the top of Clingman's 
Dome (about 2080 m) in the Great Smoky Mountains National Park, the annual 
mean wind speed in 1981 was 3.2 m/s at a height just above the forest canopy 
(D. Holland, National Park Service, pers. coram.). At the NOAA Oak Ridge, 
Tennessee, weather station (300 m elevation), the annual mean wind speed 
is 2 m/s at the top of a 10-m tower in an open area (NOAA 1981). If the 
Clingman's Dome anemometer were also located 10 m above the momentum- 
absorbing surface (the zero-plane displacement height of the canopy), then 
the difference between the sites would be much more striking. Wind speeds 
affect dry deposition in several ways. For particles large enough for 
inertial impaction on vegetation surfaces, increases in wind speed cause 
increased particle momentum and thus increased efficiency of impaction 
(Chamberlain 1975). For smaller particles and gases, the wind speed effect 
is less dramatic, but involves reduction in the width of the aerodynamic 
boundary layer through which the depositing material must pass. 



227 



Humidity also affects dry deposition. Hygroscopic particles (including 
many common pollutants such as salts of SO^-, NO3 - , and Pb) swell in size 
in higher humidities, and are deposited more efficiently. Gaseous deposition 
to plants has also been shown to increase under high humidity regimes 
(McLaughlin and Taylor 1981) . Because of decreases in temperature, with 
increasing elevation, relative humidities tend to increase, although some 
low-elevation hollows may have higher humidities because of cold air 
drainage (Geiger 1965) . Data to support this humidity trend in the 
southern Appalachians are not available. 

The nature of the vegetation cover can also change with elevation and 
affect dry deposition. If upper slopes are dominated by needle-leaved, 
evergreen forests, and lower slopes by broad-leaved deciduous forests, 
dry deposition to the upper slopes could be greater for two reasons. First, 
evergreen forests present a high surface area for dry deposition throughout 
the year, as opposed to the winter season defoliation of deciduous trees. 
Second, needles have a higher capture efficiency for small particles than do 
broad leaves (Belot and Gauthier 1975). 

Changes in wind speed, humidity, and vegetation type therefore suggest 
higher rates of dry deposition at higher elevations. If higher elevations 
have better air quality, this effect could be reduced. However, because 
of a lack of conclusive evidence of elevational effects on air quality, a 
higher dry deposition load at high elevations is hypothesized. The current 
state of measurement capability for dry deposition suggests that it may be 
some time before this hypothesis can be tested conclusively for all major 
pollutants. Taylor and Parr (1983) measured fluoride in white pine ( Pinus 
strobus) and hemlock (Tsuga canadensis) foliage at elevations of 600, 850, 
and 1300 m on a west-facing slope in the Great Smoky Mountains National Park. 
This slope had a windward exposure to potential regional sources of 
particulate and gaseous fluorides, including coal combustion, aluminum 
smelting, and uranium enrichment. No significant differences in foliar 
fluoride were found between the two lower elevations for either species, 
but concentrations found at the 1300-m site exceeded those at 600 m by 
factors of 1.5 to 2.5 and varied with species and needle age. Another recent 
study suggests the importance of dry deposition in a high-elevation ecosystem 
in the western United States. Graustein and Armstrong (1983) used strontium 
isotope ratios to show that the spruce-fir forests of the mountains of 
northern New Mexico are growing on a mantle of material derived from the 
surrounding lowlands and transported as wind-blown dust. This is undoubtedly 
an extreme case, occurring in a windy, arid environment, but it indicates 
the potential significance of dry deposition at high elevations. 

CLOUD WATER DEPOSITION 

The deposition of cloud droplets does not fit well into either the wet or 
dry deposition categories. Pollutant material is delivered in solution, 



228 



but the mechanisms of deposition (turbulent transport, impaction, 
sedimentation) are more characteristic of large suspended particles than 
of precipitation. At low elevations, fogs (defined as ground-level clouds) 
are formed chiefly by radiative cooling of the surface. These fogs are 
associated either with no wind, in the case of level terrain, or with very 
slight winds in the case of cold air drainage on hillslopes. In contrast, 
high elevation fogs are usually either orographic (caused by air rising 
up the windward slope of a mountain) or are the result of low-level stratus 
clouds whose base is below the height of the mountains. In either case, 
the fogs are usually associated with the high winds characeristic of 
mountaintops . These winds add momentum to the droplets and increase their 
ability to impact on vegetation surfaces (Thorne et al . 1982). In addition, 
the fog frequency on eastern mountains can be very high; the summit of 
Mt . Washington, New Hampshire, is in clouds 50 percent of the time (Reincrs 
and Lang 1979). The concentrations of dissolved substances in cloud water 
tend to be several times higher than those in rain of the same area 
(Waldman et al . 1982, Lovett et al. 1982, Falconer and Kadlecek 1980), 
probably because the cloud droplets have a longer residence time in the 
atmosphere. Taken together, these factors suggest that cloud water is 
an important vector of pollutant deposition at high elevations. 

Cloud water deposition has been measured by Lovett et al. (1982) on 
Mt . Moosilauke, New Hampshire. The upper slopes of Mt . Moosilauke are 
in clouds about 40 percent of the time, and average wind speeds at 1200 m 
elevation are about 5 m/s. Lovett et al. found that cloud water deposition 
was directly proportional to wind speed and the total annual deposition of 
SO4 , NO3 - , K + , Na + , and H by cloud water was greater than the deposition 
by precipitation. Dry deposition was not measured. Deposition of H + at 1200 m 
was almost four times the deposition measured at a low elevation site 13 km 
away. In the southern Appalachians, Smathers (1982) and Holland (National 
Park Service, unpublished data) reported substantial cloud deposition in 
rain gauges fitted with fog-intercepting screens. Although it is difficult 
to extrapolate from these measurements to the amount of cloud water actually 
caught by the vegetation, these studies document the existence of the cloud 
deposition phenomenon in the southeastern mountains. 

STUDIES OF LEAD DEPOSITION 

Several studies have focused on the accumulation of lead in the organic 
layers of high-elevation forest soils . Lead is released as an aerosol from 
some smelters and from automobiles burning leaded fuel, and is deposited 
by wet, dry, and cloud water deposition. The deposited lead is efficiently 
bound to organic material and thus accumulates in the forest floor; the 
extent of this accumulation has been considered a long-term record of lead 
deposition. Reiners et al. (1975) found an increase in lead contents of 
forest floors along an elevational gradient on Mt . Moosilauke, New Hampshire, 
which they attributed to increases in atmospheric deposition (wet, dry, and 
cloud water) along this gradient. The lead contents increased about fourfold 
from the hardwoods zone at approximately 700 m to the top of the fir zone 



229 



at approximately 1400 m, but decreased in the higher elevation alpine 
tundra ecosystem. This decrease was attributed to the smaller interceptive 
surface area of tundra plants, and suggests the importance of dry and cloud 
deposition, which are dependent on vegetation surfaces for deposition. 
Johnson et al. (1982) found a similar increase in forest floor lead content 
in the elevational range 300 to 1200 m in the Taconic, Green, and White 
Mountains of New England. Their analysis of buried soil horizons indicated 
that the lead content of these forest floors may have increased five to 
tenfold in the last century. Graustein and Turekian (1983) used soil 
profiles to determine the long-term average deposition rate of the natural 
radioactive isotope 210pb along elevational gradients in New Mexico and 
New Hampshire. They found that deposition increased with elevation in both 
places.. In the southern Appalachians, Turner et al . (1983) measured lead 
concentrations in forest floor horizons of the spruce-fir zone of the Great 
Smoky Mountains National Park. Their data indicate concentrations about 
one-half those reported from spruce-fir forests in the northeastern United 
States, suggesting that pollutant lead deposition may not have occurred in 
the Southern Appalchians to the extent it has in the Northeast. Lead 
contents of the forest floor were not reported, nor were elevational trends. 

CONCLUSIONS 

The studies discussed in this paper suggest an elevational increase in 
total pollutant deposition. The apportionment of this trend into components 
of wet, dry and cloud deposition cannot be clearly discerned from the 
available data; however, all three processes probably increase 
with elevation, and their relative importance may vary between different 
pollutants and different geographic areas. Further research will be necessary 
to assess fully the rates and processes of pollutant deposition in mountainous 
terrain. Data needs include high-elevation measurements of precipitation 
chemistry and amount, air pollutant concentrations, fog water chemistry, dry 
deposition rates, and meteorological variables such as fog frequency, 
wind speed, wind direction, and relative humidity. Because of their severe 
climate, mountain ecosystems may be fragile and especially susceptible to 
damage from pollutants. Although these ecosystems are frequently remote 
from large population centers, they are important to man as recreation 
areas, sources of water and reserves for unique species. The consequences 
of air pollution damage to these ecosystems are thus potentially severe. 
An accurate determination of pollutant deposition rates if necessary before 
any assessment of pollutant impacts can be made. 



230 



ACKNOWLEDGMENTS 

Support for the author was provided by the Electric Power Research Institute 
(RP1907-1) and the Office of Health and Environmental Research, U.S. Department 
of Energy. I thank J. S. Olson and F. G. Taylor for critical reviews 
of the manuscript. Oak Ridge National Laboratory (ORNL) is operated by 
Union Carbide Corporation under contract W-7405-eng-26 with the U. S. 
Department of Energy. Publication No. 2265, Environmental Sciences 
Division, ORNL. 

By acceptance of this article, the publisher or recipient acknowledges the 
U. S. Government's right to retain a nonexclusive, royalty-free license 
in and to any copyright covering the article. 



231 



LITERATURE CITED 

Belot, Y. and Gauthier, D. 1975. Transport of micronic particles from 
atmosphere to foliar surfaces. In D. A. Devries and N. H. Afgan 
(eds.) Heat and mass transfer in the biosphere. Part I. Transfer 
processes in the plant environment, p. 583-591. Washington, D.C.: 
Scripta Book Co. 

Chamberlain, A. C. 1975. The movement of particles in plant communities. 
In J. L. Monteith (ed.) Vegetation and the atmosphere. Vol. I. 
Principles, p. 155-203. N.Y. :Academic Press. 

Davidson, C.I., Wiersma, G. B., Brown, K. W., Goold , W. D., Matheson, T.P., 
and Reilly, M. T. Airborne trace elements in Great Smoky Mountains, 
Olympic and Glacier National Parks. Environmental Sci. and Tech . 
(in press) . 

Dingman, S. L. 1979. Elevation: A major influence on the hydrology 
of New Hampshire and Vermont, U.S.A. In Preprint volume. Third 
conference on hydrometerology , p. 4-11. Amer. Met. Soc . , Boston. 

Duchelle, S.F., Skelly, J. M., and Chevone, B. I. 1982. Oxidant effects 
on forest tree seedling growth in the Appalachian Mountains. Water 
Air Soil Pollut. 18:363-373. 

Environmental Protection Agency (EPA). 1983. The acidic deposition 
phenomenon and its effects. Vol. I. Atmospheric sciences. 
EPA-600/8-83-016A. U.S.E.P.A., Washington, D.C. 

Falconer, P.D. and Kadlecek, J. A. 1980. Cloud chemistry and 

meteorological research at Whiteface Mountain, summer 1979. ASRC 
Publ. No. 748. Atmos. Seci. Res. Ctr., Albany, N.Y. 

Geiger, R. 1965. The climate near the ground. Boston : Harvard Univ. Press 

Graustein, W. C. and Armstrong, R. L. 1983. The use of 87 Sr/ 86 Sr ratios 
to measure atmospheric transport into forested watersheds. 
Science 219:289-292. 

Graustein, W. C. and Turekian, K. K. 1983. 210 Pb as a tracer of the 
deposition of sub-micrometer aerosols. In H. R. Pruppacher, 
R. G. Semonin and W. G. N. Slinn (eds.) Precipitation scavenging, 
dry deposition, and resuspension, p. 1315-1324. Elsevier, N. Y. 

Hicks, B. B. and Shannon, J. D. 1979. A method for modeling the 
deposition of sulfur by precipitation over regional scales. 
J. Appl. Meterol. 18:1415-1420. 

Hosker, R. P., Jr. and Lindberg, S. E. 1982. Review: Atmospheric 

deposition and plant assimilation of gases and particles. Atmos. 
Environ. 16:889-910. 



232 



Johnson, A. H., Siccama, T. G., and Friedland, A. J. 1982. Spatial 

and temporal patterns of lead accumulation in the forest floor in 
the northeastern U.S. J. Environ. Qual. 11:577-580. 

Knutson, E. 0. and Stockham, J. D. 1977. Aerosol scavenging by snow: 
comparison of single flake and entire snowfall results. in 
R. G. Semonin and R. W. Beadle (eds.) Precipitation scavenging 
(1974), p. 195-207. ERDA Sym. Ser. 41, CONF-741003, Energy Res. 
and Dev. Admin., Washington, D.C. 

Lindberg, S. E. 1982. Factors influencing trace metal, sulfate and 

hydrogen ion concentrations in rain. Atmos. Environ. 16:1701-1709. 

Lovett, G. M., Reiners, W. A., and Olson, R. K. 1982. Cloud droplet 
deposition in subalpine balsam fir forests: Hydrological and 
chemical inputs. Science 218:1303-1304. 

McLaughlin, S. B. and Taylor, G. E. 1981. Relative humidity: Important 
modifier of pollutant uptake by plants. Science 211:167-169. 

National Oceanic and Atmospheric Administration (NOAA) 1981. Local 
climatological data, Oak Ridge, Tennessee. National Climatic 
Center, Asheville, N.C. 

Raynor, G. S. and Hayes, J. V. 1983. Differential rain and snow 

scavenging efficiency implied by ionic concentration differences 
in winter precipitation. In H. R. Pruppacher , R. G. Semonin, and 
W. G. N. Slinn (eds.) Precipitation scavenging, dry deposition, 
and resuspension, p. 249-264. Elsevier, N.Y. 

Reiners, W. A. and Lang, G. E. 1979. Vegetational patterns and 

processes in the balsam fir zone, White Mountains, New Hampshire. 
Ecology 60:403-417. 

Reiners, W. A., Marks, R. H. and Vitousek, P. M. 1975. Heavy metals 

in subalpine and alpine soils of New Hampshire. Oikos 26:264-275. 

Sehmel, G. A. 1980. Particle and gas dry deposition: A review. 
Atmos. Environ. 14:983-1012. 

Shanks, R. E. 1954. Climates of the Great Smoky Mountains. Ecology 
35:354-361. 

Skelly, J.M., Chevone, B. I. and Yang, Y. S. 1983. Effects of ambient 

concentrations of air pollutants on vegetation indigenous to the Blue 
Ridge Mountains of Virginia. In P. Herrmann and A. I. Johnson (eds.) 
Acid rain: A water resource issue for the 80's. p. 69-73. Amer. 
Water Resour. Assoc., Bethesda, Md . 



233 



Smathers, G. A. 1982. Fog interception at high elevations of the Blue 

Ridge Parkway in North Carolina. In Eighth Annual Scientific Research 
Meeting. Great Smoky Mountains National Park, June 24-25, 1982. 
p. 49. NPS SE Office, Atlanta, GA. 

Stevens, R. K. , Dzubay, T. G., Shaw, R. W. , McLenny, W. A., and Lewis, C. W. 
1980. Characterization of the aerosol in the Great Smoky Mountains. 
Environ. Sci. and Technol. 14:1491-1498. 

Taylor, F. G. and Parr, P. D. 1983. Fluoride survey in the Great Smoky 
Mountains vegetation and soils. Final report, Interagency Agreement 
40-1249-82, Air Quality Division, U. S. NPS. 

Tennessee Valley Authority (TVA) 1983. Investigations of the cause of 
fish kills in fish-rearing facilities in Raven Fork Watershed. 
TVA/0NR/WR-83/9. Office of Nat. Res., TVA, Knoxville, TN . 

Thorne, P. G., Lovett, G. M., and Reiners, W. A. 1982. Experimental 

determination of droplet impaction on canopy components of balsam fir. 
J. Appl. Meteorol. 10:1413-1416. 

Turner, R. R., Bogle, M. A., and Baes, C. F. III. 1983. Lead in vegetation, 
forest floor, and soils of the spruce-fir zone of the Great Smoky 
Mountains National Park. Abstract of paper presented at 9th Annual 
Scientific Research Meeting, Great Smoky Mountains National Park, 
May 19-20, 1983. 

Waldman, J. D., Munger, J. W. , Jacobs, D. J., Flagan, R. C, Morgan, J. J., 
and Hoffman, M. R. 1982. Chemical composition of acid fog. Science 
218:677-680. 



214 



APPENDIX I. 

VASCULAR PLANTS 
OF SOUTHERN APPALACHIAN SPRUCE-FIR: 
ANNOTATED CHECKLISTS ARRANGED BY GEOGRAPHY, 
HABITAT, AND GROWTH FORM 



P. S. White and L. A. Renfro 



These lists are arranged by geographic area, habitat, and 
growth form. Three geographic categories are used: (1) Great 
Smoky Mountains National Park, (2) additional southern 
Appalachian high peak areas, and (3) northern Appalachians. For 
Great Smoky Mountains National Park, five habitat categories are 
used: (1) spruce-fir forest, (2) wet sites (seepage areas, wet 
thickets, streamsides) , (3) high elevations cliffs, (4) heath 
balds, and (5) trailsides (within spruce-fir). Grassy balds are 
not covered here because they have been treated in detail 
elsewhere (for a recent compilation see D. A. Stratton and P. S. 
White, 1982, National Park Service, Southeast Regional Office, 
Res ./Resource Manage. Rept . SER-58) and because they are not 
always adjacent to spruce-fir forest (which is the central 
habitat type for these lists). For all lists, five growth form 
categories are used: (1) trees, (2) small trees, (3) shrubs, (4) 
dwarf shrubs, and (5) herbs (the latter divided into 
pteridophytes , graminoids, and forbs) . 

The following annotations are used to show frequency in 
spruce-fir forest, geographical distributions, and 'listed' 
status: 

+ Species characteristic of Appalachian spruce-fir (hence 
used only for the spruce-fir habitat category) 

( ) Species characteristic of northern hardwood forest or 
other vegetation type adjoining spruce-fir and usually 
found only at low elevations within spruce-fir 
dominated forests 

N Species found in the northern Appalachians 

S Species found in the southern Appalachians 

-rare Species significantly rare in either north (N-rare) 
or south (S-rare) 

-endemic Species endemic to the high elevations of the 
southern Appalachians (Note that this category includes 
only the high elevation endemics. For example, if a 
particular species is endemic to the southern 

235 



Appalachians but occurs throughout the elevation 
gradient it would be designated "S" only. If the 
species were endemic to the high elevations it would be 
designated "S-endemic" . ) 

-listed Species found on state or national rare and 
endangered species lists (from unpublished data of P. 
S. White; this designation is applied to GRSM plants 
only) 

* Introduced species 

The continuous nature of compositional change with elevation 
means that an arbitrary line must be drawn between extraneous 
floristic elements only rarely present in spruce or spruce-fir 
communities and those that can be considered recurrent enough to 
warrant inclusion in these lists. For example, Fagus qrandif olia 
(beech) stands occur adjacent to the lower elevation limit of 
spruce-fir forests and saplings of this species are occasion 
seen in adjacent spruce-fir — hence this species appears as 
"(Fagus grandif olia) " in the checklist. On the other hand a 
number of lower elevation species have been excluded from the 
lists even though they may be seen, though rarely, within or 
immediately adjacent to spruce-fir forests. These include: 
Allium tricoccum, Aquilegia canadensis , Castanea dentata, 
Caulophyllum thalictroides , Crataegus macrosperma, Cr yptotaenia 
canadensis , Erigeron pulchellus , Fraxinus amer icana. Geranium 
maculatum, Osmorhiza claytonii , Pinus pungens , Polyst ichum 
acrostic ho ides , Smilax rotundif olia , and Vicia caroliniana . 
Spruce or spruce-fir dominated stands adjoin several community 
types: northern hardwoods (on moist and protected sites), 
hemlock (on north facing open slopes and ridges) , heath balds (on 
exposed ridges) , pine-heath (on exposed ridges) , and oak (on 
upper flats and some south facing slopes) . Species from each of 
these community types may also be found occasionally in adjacent 
spruce-fir forests. 

There are also northern species and high elevation southern 
Appalachian endemic species which, though found in GRSM, are not 
known to occur within the spruce-fir type. Some of these cannot 
be assigned a habitat because collection data are imprecise 
(e.g., Linnaea borealis and Lilium gravi ) . Others are found in 
the GRSM flora, but not in any of the habitat types considered 
here (e.g., Agrostis borealis , Carex trisperma, Coeloglossum 
virescens , Corvlus cornuta , Hieracium scabrum. Ilex collina , 
Lilium canadense , and Lycopodium annotinum ) . These species are 
not listed below, despite their association in other parts of 
their ranges with the habitat categories we have used. 

Species listed under "Northern Appalachian species not found 
in southern Appalachian spruce-fir" may be found in areas 
adjacent to the southern Appalachian high peaks but are not found 
in the high elevation areas we focus on here. The southern 
Appalachian high peaks are those areas that surpass 1,680 m (5500 
ft) in elevation (see Saunders, this volume, Ramseur 1960). Some 



236 



species listed as not found in southern Appalachian spruce-fir 
are native in the state of Virginia (e.g., Trientalis borealis ) 
or West Virginia (e.g., Cornus canadensis ) . Quite a few of the 
species are found in the central Appalachians (e.g., Shenandoah 
National Park, Virginia, where Abies balsamea is found). These 
northern species may also be found in the south in association 
with habitats other than spruce-fir forest (e.g., bogs near the 
glacial boundary) . In any case, they are generally distributed 
in spruce-fir communities in the northeast. As in the Great 
Smoky Mountains National Park checklist, those that are typical 
of upland northern Appalachian slope forests are designated by a 
" + " sign. 

If species designated with " — S n occur in the north, but 
are not associated with spruce-fir vegetation there, then no "N" 
appears in the annotations (e.g., Euonymus obovatus ) . 

These lists are compiled from unpublished data of P. White 
and the following published sources: 

Oosting, H. J., and D. W. Billings. 1951. A comparison 
of virgin spruce-fir forest in the northern and 
southern Appalachian system. Ecol. 32:84-103. 

Ramseur, G. S. 1960. The vascular flora of the high 
mountain communities of the southern Appalachians. J. 
Elisha Mitchell Sci. Soc . 76:82-112. 

White, P. S. 1976. The upland forest vegetation of the 
Second College Grant, New Hampshire. Ph. D. 
Dissertation, Dartmouth College, Hanover, N.H. 294 p. 

White, P. S. 1982. The flora of Great Smoky Mountains 
National Park: an annotated checklist of the vascular 
plants and a review of previous floristic work. 
National Park Service, Southeast Region, Res ./Resource 
Manage. Rept. SER-55. 219 p. 



237 



A. CHECKLISTS FOR GREAT SMOKY MOUNTAINS NATIONAL PARK 
1. SPRUCE-FIR FORESTS 
TREES: 

+Abies fraseri — S-endemic; listed 

Acer rubrum — N,S 

(Acer saccharum — N,S) 

(Aesculus octandra — S) 

Betula cordifolia — N,S-rare; listed 
+Betula lutea — N,S 

(Fagus grandifolia — N,S) 
+Picea rubens — N,S 

(Prunus serotina — N,S) 

Tsuga canadensis — N,S 

SMALL TREES: 

Amelanchier laevis — N r S 

Acer pensylvanicum — N,S 
+Acer spicatum — N,S 

Prunus pensylvanica — N,S 
+Sorbus americana — N,S 

SHRUBS: 

Aronia melanocarpa — N,S 

(Cornus alternifolia — N,S) 

Diervilla sessilifolia — S-endemic 

(Euonymus obovatus — S; listed) 

(Hydrangea arboresences — S) 

Ilex montana — S 

Lonicera canadensis — N,S-rare; listed 

Menziesia pilosa — S-endemic; listed 
+Rhododendron catawbiense — S 

Rhododendron maximum — S 
+Ribes glandulosum — N,S 
+Ribes rotundifolium — S-endemic 
+Rubus canadensis — N,S 

Rubus idaeus var . canadensis — N,S-rare; listed 
+Sambucus pubens — N,S 

Vaccinium constablaei — S 
+Vaccinium erythrocarpon — S-endemic 
+Viburnum alnifolium — N,S 

Viburnum cassinoides — N,S 

DWARF SHRUBS: 

(Gaultheria procumbens — N,S) 
(Mitchella repens — N,S) 



238 



HERBS: 

Pteridophytes: 

Asplenium montanum — S 
+Athyrium asplenioides — S 

Athyrium thelypteroides — N,S 

(Botrychium virginianum — N,S) 

Cystoperis protrusa — S 
+Dennstaedtia punctilobula — N,S 
+Dryopteris campyloptera — N,S 
+Dryopteris intermedia — N,S 

Lycopodium clavatum — N,S 
+Lycopodium lucidulum — N,S 

Lycopodium obscurum — N,S 

Osmunda cinnamomea — N,S 

Osmunda claytoniana — N,S 

Polypodium virginianum — N,S 

(Pteridium aquilinum — N,S) 

Thelypteris noveboracensis — N,S 

Thelypteris phegopteris — N,S-rare; listed 

Graminoids: 

Brachyelytrum erectum — N,S 

Carex aestivalis — N,S 
+Carex brunnescens — N,S 

Carex communis — N,S 
+Carex debilis — N,S 
+Carex intumescens — N,S 

Carex laxiflora — N,S 

Carex misera — S-endemic; listed 
+Carex pensylvanica — N,S 

Carex projecta — N,S 
+Cinna latifolia — N,S 

(Danthonia compressa — N,S) 

(Festuca obtusa — N-rare, S) 

Glyceria melicaria — N,S 

Glyceria nubigena — S-endemic-rare; listed 

Luzula acuminata — N,S 

Luzula echinata — S 

Milium effusum — N,S-rare; listed 

Poa alsodes — N,S 

Forbs: 

Amianthemum muscaetoxicum — S 
+Anemone quinquefolia — N,S 
+Angelica triquinata — S-endemic 

Arabis laevigata — S 

Aralia nudicaulis — N,S 
+Arisaema triphyllum — N,S 
+Aster acuminatus — N,S 
+Aster chlorolepis — S-endemic 

Aster cordifolius — N,S 



239 



+Aster curtisii — S 

Aster macrophyllus — N,S 

Cacalia atriplicif olia — S 
+Cacalia rugelia — S-endemic; listed 

Chelone lyoni — S-endemic 
+Cimicifuga americana — S 

Circaea alpina — N,S 

Claytonia caroliniana — N,S 
+Clintonia borealis — N,S 

Cuscuta rostrata — S 

(Cypripedium acaule — N,S) 

Dentaria diphylla — N f S 

(Dicentra canadensis — N,S) 

(Dicentra cucullata — N,S) 

Erythronium americanum — N,S 

(Eupatorium purpureum — S,N-rare) 
+Eupatorium rugosum — N,S 

(Galax aphylla — S) 

Galium triflorum — N,S 

Goodyera repens var. ophioides — N,S 

Heuchera americana — S 

Heuchera villosa — S 

Houstonia purpurea — S 
+Houstonia serpyllif olia — S-endemic 
+Impatiens pallida — N,S 
+Laportea canadensis — N,S 

Lilium superbum — S 

Listera smallii — S 

Maianthemum canadense — N,S 
+Medeola virginiana — N,S 

(Melantium parviflorum — S) 

(Monarda didyma — S) 
+Monotropa uniflora — N,S 
+Oxalis montana — N,S 

(Phacelia fimbriata — S) 

Platanthera psycodes — N,S 

(Podophyllum peltatum — N,S) 

(Polygonatum pubescens — N,S) 

Polygonum cilinode — N,S-rare; listed 

(Potentilla simplex — N,S) 
+Prenanthes altissima — N,S 

Prenanthes roanensis — S-endemic; listed 

(Ranunculus recurvatus — N,S) 

Rudbeckia laciniata — S 

Saxifraga michauxii — S-endemic 

(Smilacina racemosa — N,S) 

Smilax herbacea — N,S 
+Solidago curtissii — S 
+Solidago glomerata — S-endemic 

Stachys clingmanii — S-endemic; listed 

Streptopus amplexif olius — N,S-rare; listed 
+Streptopus roseus — N,S 

(Tiarella cordifolia — N,S) 

(Trautvetteria caroliniensis — S) 
+Trillium erectum — N,S 



240 



Trillium undulatum — N,S 

(Uvularia perfoliata — N,S) 
+Veratrum viride — N,S 
+Viola mackloseyi ssp. pallens — N,S 
+Viola papilionacea — N,S 

(Viola rotundifolia — N,S) 

2. SEEPAGE AREAS, STREAMSIDES, AND WET THICKETS 

SHRUBS: 

Aronia melanocarpa — N,S 
Salix humilis — N,S 
Salix sericea — N f S 
Sambucus pubens — N,S 
Viburnum cassinoides — N,S 

HERBS: 

Graminoids: 

Carex crinita — N,S 

Carex normalis — N,S 

Carex ruthii — S-endemic; listed 

Carex scabrata — N,S 

Carex stipata — N,S 

Carex tribuloides — N,S 

Glyceria nubigena — S-endemic-rare; listed 

Glyceria striata — N,S 

Juncus effusus — N,S 

Forbs: 

Aconitum uncinatum — S 
Aster puniceus — N,S 
Chelone lyoni — S-endemic 
Cardamine clematitis — S 
Chrysosplenium americanum — N,S; listed 
Cirsium muticum — N,S 
Diphylleia cymosa — S 
Eupatorium fistulosum — N,S 
Eupatorium maculatum — N,S 
Hypericum graveolens — S-endemic; listed 
Hypericum mitchellianum -- S-endemic; listed 
Hypericum mutilum — N,S 
Impatiens capensis — N,S 
Lycopus virginicus — N,S 
Monarda didyma — S 
Parnassia asarifolia — S 
Platanthera clavellata — N,S 
Platanthera psycodes — N,S 
Rudbeckia laciniata — S 
*Rumex obtusifolius — N,S 
Saxifraga micranthidif olia — S 
Stachys clingmanii — S-endemic 



241 



Thalictrum clavatum — S 
Thalictrum polygamum — N,S 
Veratrum viride — N,S 
Viola mackloskeyi ssp. pallens — N,S 
Viola papilionacea — N,S 

3. HEATH BALDS 

SHRUBS: 

Aronia melanocarpa — N,S 

Diervilla sessilifolia — S-endemic 

Clethra acuminata — S 

Ilex montana — S 

Kalmia latifolia — S 

Leiophyllum buxifolium — S 

Leucothoe editorum — S 

Lyonia ligustrina — N,S 

Menziesia pilosa — S-endemic; listed 

Pieris floribunda — S 

Rhododendron catawbiense — S 

Rhododendron maximum — S 

Rhododendron minus — S 

Vaccinium constablaei — S 

Viburnum cassinoides — N,S 

DWARF SHRUBS: 

Epigaea repens — N,S 
Gaultheria procumbens — N,S 

HERBS: 

Pteridophytes: 

Lycopodium f labellif orme — N,S 
Lycopodium tristachyum — N,S 
Pteridium aquilinum — N,S 

Forbs: 

Galax aphylla — S 
Melampyrum lineare — N,S 

4. HIGH ELEVATION CLIFFS 

SHRUBS: 

Diervilla sessilifolia — S-endemic 

Leiophyllum buxifolium — S 

Menziesia pilosa — S-endemic; listed 

Rhododendron catawbiense — S 

Rhododendron minus — S 

Vaccinium angustif olium — N,S-rare; listed 



242 



HERBS: 

Pteridophytes: 

Asplenium montanum — S 
Asplenium trichomanes — N,S 
Lycopodium selago — N,S-rare; listed 
Polypodium virginianum — N,S 

Graminoids: 

Calamagrostis cainii — S-endemic-rare; listed 

Carex misera — S-endemic; listed 

Carex ruthii — S-endemic; listed 

Glyceria nubigena — S-endemic-rare; listed 

Juncus trifidus var. monanthos — S-endemic-rare; listed 

Scirpus caespitosus — N,S-rare; listed 

Forbs: 

Cardamine clematitis — S 

Chelone lyoni — S-endemic 

Gentiana linearis — N,S-rare; listed 

Geum radiatum — S-endemic-rare; listed 

Hypericum graveolens — S-endemic; listed 

Hypericum mitchellianum — S-endemic; listed 

Krigia montana — S-endemic-rare; listed 

Parnassia asarifolia — S-rare 

Saxifraga michauxii — S-endemic 

Solidago glomerata — S-endemic 

5. TRAILSIDES WITHIN SPRUCE-FIR FORESTS 

HERBS: 

Graminoids: 

Agrostis perennans — N,S 
*Holcus lanatus — N r S 

Juncus tenuis — N,S 
♦Poa annua — N,S 
*Poa pratense — N,S 

Forbs: 

♦Achillea millefolium — N,S 
♦Barbarea vulgaris — N,S 
♦Chrysanthemum leucanthemum — N,S 

Fragaria virginiana — N,S 

Plantago rugelii — N,S 
♦Prunella vulgaris — N,S 

Ranunculus spp — N,S 
♦Rumex acetosella — N,S 
♦Trifolium spp — N,S 
♦Veronica officinalis — N,S 

243 



B. ADDITIONAL SOUTHERN APPALACHIAN HIGH ELEVATION SPECIES NOT 

FOUND IN GREAT SMOKY MOUNTAINS NATIONAL PARK 

TREES: 

Tsuga caroliniana — S 

SHRUBS: 

Alnus crispa — N,S-rare; listed 
Comptonia peregrina — N,S-rare; listed 
Diervilla lonicera — N,S-rare; listed 
Potentilla tridentata — N, S-rare; listed 
Rhododendron vaseyi — S-endemic-rare; listed 

HERBS: 

Pteridophytes: 

Selaginella tortipilla — S-rare 

Graminoids: 

Agrostis borealis — N, S-rare; listed 
Calamagrostis canadensis — N, S-rare; listed 
Carex biltmoreana — S-endemic-rare 
Deschampsia flexuosa — N,S 
Trisetum spicatum var. molle — N, S-rare; listed 

Forbs: 

Arenaria groenlandica — N r S-rare; listed 

Cardamine pensylvanica — N, S-rare; listed 

Corallorhiza maculata — N f S-rare 

Epilobium angustif olium — N, S-rare; listed 

Gentiana andrewsii — S-endemic-rare 

Geum geniculatum — S-endemic-rare; listed 

Houstonia montana — S-endemic-rare; listed 

Hypericum buckleyi — S-endemic-rare; listed 

Hypericum canadense — N, S-rare 

Liatris helleri — S-rare 

Sedum telephioides — S-rare 

Sedum rosea var. roanensis — S-endemic-rare 

Solidago spithamea — S-rare 

C. NORTHERN APPALACHIAN SPRUCE-FIR FOREST SPECIES NOT FOUND IN 

SOUTHERN APPALACHIAN SPRUCE-FIR 

TREES: 

+Betula papyrifera 
Larix laricina 
Picea mariana 
Pinus banksiana 



244 



Pinus resinosa 
Populus balsamif era 
Populus tremuloides 

SMALL TREES: 

Betula populifolia 
+Sorbus decora 

SHRUBS: 

Amelanchier bartramiana 

Aralia hispida 

Diervilla lonicera 

Kalmia angustifolia 

Ledum groenlandicum 
+Nemopanthus mucronata 

Prunus virginiana 

Rhododendron canadense 

Ribes hirtellum 
+Ribes lacustre 

Ribes triste 
+Rubus pubescens 

Salix bebbiana 

Salix discolor 

Salix pyrifolia 

Salix rigida 
+Vaccinium myrtilloides 

DWARF SHRUBS: 

Chimaphila umbellata 
+Chiogenes hispidula 
+Linnaea borealis 

HERBS: 

Pteridophytes: 

Equisetum sylvaticum 
Cystopteris fragilis 
Gymnocarpium dryopteris 
+Lycopodium annotinum 

Graminoids: 

Carex canescens 
Carex trisperma 
Oryzopsis asperifolia 
Schizachne purpurascens 

Forbs: 

+Actaea rubra 
Arenaria lateriflora 



245 



Conioselinum chinense 
+Coptis groenlandica 

Corallorhiza trifida 
+Cornus canadensis 

Dalibarda repens 
+Goodyera tesselata 

Mitella nuda 

Moneses uniflora 

Platanthera macrophylla 

Platanthera orbiculata 

Pyrola asarifolia 
+Pyrola elliptica 
+Pyrola minor 
+Pyrola secunda 

Smilacina trifolia 
+Solidago macrophylla 
+Trientalis borealis 

Viola renifolia 



246 



APPENDTX II. 

BIBLIOGRAPHY OF RESEARCH 
ON SOUTHERN APPALACHIAN SPRUCE-FIR VEGETATION 



P. S. white and C. Eagar 

Vegetation is the Key component of this ecosystem: the 
analysis of forest decline, balsam woolly aphid effects, 
ecosystem effects of pollutants, and habitat change for a variety 
of plant and animal populations centers on changes in forest 
compostion, structure, and dynamics. We have compiled this 
bibliography in order to provide easy access to the already 
extensive literature on southern Appalachian spruce-fir 
vegetation. We have included population, community, and 
ecosystem oriented research; for more specialized topics see 
individual chapter bibliographies in this volume. This 
bibliography was compiled from DeYoung et al. (1982), from the 
contrioutors to this volume, and from unpublished files of the 
authors . 



247 



SOUTHERN APPALACHIAN SPRUCE-FIR: 
A BIBLIOGRAPHY 

Adams, H. S., and S. L. Stephenson. 1983. Composition, 
structure, and dynamics of spruce-fir forest on the summit 
of Mount Rogers. Va. J. Acad. Sci. 34:138. 

Af feltranger, C. E. and J. D. Ward. 1970. Evaluation of Fraser 
fir mortality on the Moses Cone Memorial Park, National Park 
Service, N. C. USDA, Forest Service, State and Private 
For., Div. of For. Pest Contr. , Asheville, N. C, Rept. 
71:1-8. 

Aldrich, R. C, and A. T. Drooz. 1967. Estimated Fraser fir 
mortality and balsam woolly aphid infestation trend using 
aerial color photography. Forest Sci. 13:300-313. 

Aliard, H. A. 1945. A second record for the paper birch, 
Betula pap yrifera . in West Virginia. Castanea 3:55-57. 

Aliard, H. A., and E. C. Leonard. 1952. The Canaan and Stony 
River valleys of West Virginia: their former magnificent 
spruce forests, their vegetation and floristics today. 
Castanea 17:1-61. 

Amman, G. D. 1962. Seasonal biology of balsam woolly aphid on 
Mt. Mitchell, North Carolina. J. Econom. Entomol. 55:96- 
98. 

Amman, G. D. 1966. Some new infestations of balsam woolly aphid 
in North Carolina, with possible means of dispersal. J. 
Econ. Ent. 59:508-511. 

Amman, G. D. 1967. Effect of -29 degr. F. on wintering 
populations of the balsam woolly aphid in North Carolina. 
J. Econom. Entomol. 60:1765-1766. 

Amman, G. D. 1970. Phenomena of Adelqes piceae populations in 
North Carolina. Ann. Entomol. Soc. Amer. 63:1727-1734. 

Amman, G. D. and C. F. Speers. 1965. Balsam woolly aphid in the 
southern Appalachians. J. Forestry 63:18-20. 

Amman, G. D., and R. L. Talerico. 1967. Symptoms of infestation 
by the balsam woolly aphid displayed by Fraser fir and 
bracted balsam fir. USDA, Forest Service, Res. Note SE-85. 
7 p. 

Anderson, L. E. 1970. Geographical relationships of the mosses 
of the southern Appalachian Mountains. In P. C. Holt (ed.), 
The distributional history of the biota of the southern 
Appalachains, Part II. Virginia Polytechnic Institute and 
State Univ. Research Division Monogr. 2. 

Anderson, L. E., and R. H. Zander. 1973. The mosses of the 

248 



soutnern Blue Ridge Province and their phytogeog raphical 
relationships. J. Elisna Mitchell Sci. Soc. 89:15-60. 

Ashe, W. W. 1922. Forest types of the Appalachians and White 
Mountains. J. Elisha Mitchell Sci. Soc. 37:183-198. 

Ayers, H. B. , and W. W. Ashe. 1902a. Description of the 
southern Appalachian forests by river oasins. Pages 69-91 in 
Message from the President of the United States (Senate 
Document No. 84) . Washington, D. C. 

Ayers, H. B., and W. W. Ashe. 1902b. Forests and forest 
conditions in the southern Appalachians. Pages 45-59 in 
Message from the President of the United States (Senate 
Document No. 84) . Washington, D. C. 

Ayers, H. B., and W. W. Ashe. 1905. The southern Appalachian 
forests. US Geological Surv. Prof. Paper 37. Washington, 
D. C. 291 p. 

Becking, R. W., and J. S. Olson. 1978. Remeasurement of 
permanent vegetation plots in the Great Smoky Mountains 
National Park, Tennessee, USA, and the implications of 
climatic changes on vegetation. Oak Ridge National Lao., 
Environmental Sci. Div., Publ. 1111, ORNL-TM-6083 . 98 p. 

Bogucki, D. J. 1970. Debris slides and flood-related damage 
with the September 1, 1951, cloudburst in the Mt. LeConte- 
Sugarland Mountain area, Great Smoky Mountains National 
Park. Ph.D. Dissertation, Univ. of Tennessee, Knoxville. 
165 p. 

Boner, R. R. 1979. Effects of Fraser fir death on population 
dynamics in southern Appalachian boreal ecosystems. MS 
Thesis, Univ. of Tennessee, Knoxville. 105 p. 

Bratton, S. P., L. L. Stromberg, and M. E. Harmon. 1982. 
Firewood-gathering impacts in backcountry campsites in Great 
Smoky Mountains National Park. Environ. Manage. 6:63-71. 

Bratton, S. P., and P. S. White. In press. Rare plant sites and 
recreation: visitation on Mt. LeConte. Proc. Conf. on 
Social Res. in Nationa] Parks and Wildland Areas. 

Bratton, S. P., P. S. White, and M. E. Harmon. 1981. 
Disturbance and recovery of plant communities in Great Smoky 
Mountains National Park: successional dynamics and concepts 
of naturalness. Pages 42-79 in M. A. Hemstrom and J. F. 
Franklin (eds.), Successional research and environmental 
pollutant monitoring associated with Biosphere Reserves. US 
National Committee for Man and the Biosphere, Washington, 
DC. 

Bratton, S. P., and P. L. Whittaker. 1977. Great Smoky Mountain 
National Park: disturbance and visitation on Mt. LeConte. 



249 



USDI , National Park Service, Southeast Region, Report for 
the Superintendant . 59 p. 

Brown, D. M. 1938. The vegetation of Roan Mountain: an 
ecological study. Ph. D. Dissertation, Duke University, 
Durham, N. C. 152 p. 

Brown, D. M. 1941. Vegetation of Roan Mountain: a 
phytosociological and successional study. Ecol. Monogr. 
11:61-97. 

Brown, D. M. 1953. Conifer transplants to a grassy bald on Roan 
Mountain. Ecology 34:614-617. 

Cain, S. A. 1930a. Certain floristic affinities of the trees 
and shrubs of the Great Smoky Mountains and vicinity. 
Butler Univ. Bot. Studies 1:129-150. 

Cain, S. A. 1930b. An ecological study of the heath balds of 
the Great Smoky Mountains. Butler Univ. Bot. Studies 1:177- 
208. 

Cain, S. A. 1930c. The vegetation of the Great Smoky Mountains: 
an ecological study. Ph. D. Dissertation, Univ. of Chicago. 
Chicago, 111. 145 p. 

Cain, S. A. 1931. Ecological studies of the vegetation of the 
Great Smoky Mountains. I. Soil reaction and plant 
distribution. Botanical Gazette 91:22-41. 

Cain, S. A. 1935a. Ecological studies of the vegetation of the 
Great Smoky Mountains. II. The quadrat method applied to 
sampling spruce and fir forest types. Amer. Midi. Nat. 
16:566-584. 

Cain, S. A. 1935b. Trees grow on stilts in the Great Smoky 
Mountains. Science News Letter 28:125. 

Cain, S. A. 1936. Ecological work on the Great Smoky Mountain 
region. Castanea 1:25-32. 

Cain, S. A. 1940. An interesting behavior of yellow birch in 
the Great Smoky Mountains. The Chicago Naturalist 3:20-21. 

Cain, S. A. 1945. A biological spectrum of the flora of the 
Great Smoky Mountains National Park. Butler Univ. Bot. 
Studies 7:11-24. 

Cain, S. A., and J. D. 0. Miller. 1933. Leaf structure of 
Rhododendro n catawbiense Michx. grown in Picea-Abies forest 
and heath communities. Amer. Midi. Nat. 14:69-82. 

Cain, S. A., and A. J. Sharp. 1938. Bryophytic unions of 
certain forest types of the Great Smoky Mountains. Amer. 
Midi. Nat. 20:249-301. 



250 



Calise, C. B. 1978. Bryophytic ecology in high elevation 
forests of West Virginia. M. S. Thesis, West Virginia 
Univ. r Morgantown. 53 p. 

Carney, C. B. 1955. Weather and climate in North Carolina. 
North Carolina Agr. Exp. Sta. Bull. 396. 

Castro, P. A. 1969. A quantitative study of the subalpine 
forest of Roan and Bald Mountains in the southern 
Appalachians. M.S. Thesis, East Tennessee State Univ., 
Johnson City, Tenn. 60 p. 

Cielsa, W. M. f and W. D. Buchanan. 1962. Biological evaluation 
of balsam woolly aphid, Roan Mt. Gardens, Toecane District, 
Pisgah National Forest, North Carolina. USDA, Forest 
Service, Div. For. Pest Manage. Rept. 62-93. 

Cielsa, W. M., H. L. Lambert, and R. T. Franklin. 1963. 
The status of the balsam woolly aphid in North Carolina and 
Tennessee. USDA, Forest Service, Div. For. Pest Manage., 
Asheville, N.C., Rept. 1-11-63. 

Ciesla, W. M., H. L. Lambert, and R. T. Franklin. 1965. Status 
of the balsam woolly aphid in North Carolina and Tennessee— 
1964. USDA, Forest Service, Rept. 65-1-1. 11 p. 

Clark, T. G. 1954. Survival and growth of 1940-1941 
experimental plantings in the spruce type in West Virginia. 
J. Forestry 52:427-431. 

Clarkson, R. B., and D. E. Fairbrothers . 1970. A seriological 
and electrophoret ic investigation of eastern North American 
Abies (Pinaceae) . Taxon 19:720-727. 

Clovis, J. F. 1979. Tree importance values in West Virginia red 
spruce forests inhabited by the Cheat Mountain salamander. 
Proc. W. Va. Acad. Sci. 51:58-64. 

Coiles, T.S. 1938. Podzoi soils of the southern Appalachian 
mountains. Soil Sci. Soc. Amer. Proc. 3:274-279. 

Cooper, A. W. 1979. The natural vegetation of North Carolina. 
Proc. of the 16th Intern. Phytogeogr. Excursion (IPE) 1978. 
1:70-78. 

Core, E. L. 1929. Plant ecology of Spruce Mountain, West 
Virginia. Ecology 10:1-13. 

Core, E. L. 1932. Some aspects of the phytogeog raphy of West 
Virginia. Torreya 32:65-71. 

Core, E. L. 1943. Botanizing in the higher Alieghenies. Sci. 
Monthly 57:119-125. 



251 



Core, E. L. 1950. Notes on the plant geography of West 
Virginia. Castanea 15:61-79. 

Core, E. L. 1952. Botanizing on Panther Knob, West Virginia. 
Wild Flower 28:35-38. 

Core, E. L. 1966. The vegetation of West Virginia. McClain 
Printing Co., Parsons, W. Va. 217 p. 

Core, E. L. 1970. The botanical exploration of the southern 
Appalachians. In P. C. Holt (ed.), The distributional 
history of the biota of the southern Appalachians. Part II: 
Flora. Virginia Polytechnic Institute and State Univ., 
Blacksburg, Virginia, Research Division Monogr. 2:1-65. 

Cost, N. D. 1975. Forest statistics for the mountain region of 
Nortn Carolina, 1974. USDA, Forest Service, Southeast For. 
Exp. Sta., Res. Bull. SE-31. 33 p. 

Crandali, D. L. 1957. Ground vegetation patterns of the spruce- 
fir area of the Great Smoky Mountains National Park. Ph. D. 
Dissertation, Univ. of Tennessee, Knoxville. 117 p. 

Crandali, D. L. 1958. Ground vegetation patterns of the spruce- 
fir area of the Great Smoky Mountains National Park. Ecol. 
Monogr. 28:337-360. 

Crandali, D. L. 1960. Ground vegetation patterns of the spruce- 
fir area of Great Smoky Mountains National Park. Va. J. 
Sci. 11:9-18. 

Crandali, D. L. 1965. Ecological studies in the Great Smoky 
Mountains. Assoc. Southeastern Biol. Bull. 12:63-65. 

Cruickshack, J. W. 1941. Forest resources of the mountain 
region of North Carolina. USDA, Forest Service, 
Appalachian For. Fxp. Sta., For. Surv. Release 7. 55 p. 

Culver, D. C. 1981. Markovian processes in spruce-fir. Amer. 
Natur. 117:572-574. 

Darlington, H. C. 1943. Vegetation and substrate of Cranberry 
Glades, West Virginia. Bot. Gazette 104:371-393. 

Davis, J. H., Jr. 1929. Vegetation of the Black Mountains of 
North Carolina. Ph. D. Dissertation, Univ. of Chicago, 
Chicago, 111. 130 p. 

Davis, J. H., Jr. 1930. Vegetation of the Black Mountains of 
North Carolina: an ecological study. J. Elisha Mitchell 
Sci. Soc. 45:291-318. 

Delcourt, H. R., D. C. West, and P. A. Deicourt. 1981. Forests 
of the southeastern United States: quantitative maps for 
above ground woody biomass, carbon, and dominance of major 

252 



tree taxa. Ecology 62:879-887. 

Delcourt, P. A., and H. R. Delcourt. 1979. Late Pleistocene and 
Hoiocene distributional history of the deciduous forest in 
the southeastern United States. Veroff. Geobot. Inst. ETH., 
Stiftung Rubel, Zurich 68:79-107. 

DeSelm, H. R. , and G. M. Clark. 1983. Potential national 
natural landmarks of the Appalachian ranges natural region 
of the eastern United States. USDI , National Park Service, 
Washington, D. C. 

DeVore, J. E. 1972. Fraser fir in the Unicoi Mountains. 
Castanea 37:148-149. 

Dey, J. P. 1978. Fruticose and foliose lichens of the high 
mountain areas of the southern Appalachians. Bryologist 
81:1-93. 

Dey, J. P. 1979. Notes on fruticose and foliose lichen flora of 
North Carolina and adjacent mountain areas. In Proc. of the 
16th International Phytogeogr. Excursion (IPE) 1978. 1:85- 
205. 

DeYoung, H. R. , P. S. White, and H. R. DeSelm. 1982. Vegetation 
of the southern Appalachians: an indexed bibliography, 1805- 
1982. USDI, National Park Service, Southeast Regional 
Office, Res. /Resources Manage. Rept. SER-63. 94 p. 

Dickson, R. R. 1960. Some climate-altitude relationships in the 
southern Appalachian Mountain region. Bull. Amer. Meteorol. 
Soc. 40:352-359. 

Donley, D. E., and R. L. Mitchell. 1939. The relation of 
rainfall to elevation in the southern Appalachian region. 
Trans. Amer. Geophys. Union 20:711-721. 

Duerr, W. A. 1951. Forest statistics for eastern Tennessee. 
USDA, Forest Service, Southeast For. Exp. Sta., For. Surv. 
Release 66. 25 p. 

Dugger, S. M. 1892. The Balsam Groves of the Grandfather 
Mountains. P. 144-160 in, Journal of Andre' Michaux, J. B. 
Lippincott, Philadelphia, Pa. 

Duncan, W. R. 1933. Ecological comparison of leaf structures of 
Rhododendron punc tatum Andr. Amer. Midi. Nat. 14:83-96. 

Eagar, C. 1978. Distribution and characteristics of balsam 
woolly aphid infestation in the Great Smoky Mountains. M. 
S. Thesis, Univ. of Tennessee, Knoxville. 72 p. 

Eggleston, W. W. 1908. A trip to Mount Mitchell. Vermont 
Botanical Club Bull. 3:40-42. 



253 



Fedde, G. F. 1973a. Cone production in Fraser firs infested by 
the balsam woolly aphid, Adelges pi ceae (Homoptera: 
Phylloxeridae) . J. Georgia Entomolog. Soc. 8:127-130. 

Fedde, G. F. 1973b. Impact of the balsam woolly aphid on cones 
and seed produced by infested Fraser fir. Can. Entomoi. 
105:673-680. 

Fedde, G. F. 1974. A bark fungus for identifying Fraser fir 
irreversibly damaged by the balsam woolly aphid, Ade lges 
piceae . J. Ga. Entomoi. Soc. 9:64-68. 

Feidkamp, S. M. 1984. Revegetation of upper elevation deoris 
slide scars on Mount LeConte in the Great Smoky Mountains 
National Park. M. S. Thesis, Univ. of Tennessee, Knoxville. 
107 p. 

Fosberg, F. R. , and E. H. Walker. 1941. A preliminary checklist 
of plants in the Shenandoah National Park, Virginia. 
Castanea 6:89-136. 

Fox, F. J. 1977. Alternation and coexistence of tree species. 
Amer. Natur. 111:69-89. 

Frothingham, E. H. 1924. New forests for cut-over and burned 
spruce lands in the southern Appalachians. USDA, Forest 
Service, Appalach. For. Exp. Sta., Official Record, December 
10, 1924. 

Frothingham, E. H. 1931. Timber growing and logging practice in 
the southern Appalachian region. USDA, Tech. Bull. 250. 93 

P. 

Frothingham, E. H. 1943. Some observations on cut-over forests 
in the southern Appalachians. J. Forestry 41:496-504. 

Frothingham, E. H., J. S. Holmes, W. J. Damtoft, E. F. McCarthy, 
and C. F. Korstian. 1926. A forest type classification for 
the southern Appalachian mountains and adjacent plateau and 
coastal region. J. Forestry 24:673-684. 

Fuller, R. D. 1977. Why does spruce not invade the high 
elevation beech forests of the Great Smoky Mountains? M. S. 
Thesis, Univ. of Tennessee, Knoxville. 65 p. 

Fulling, E. H. 1936. Abie s intermedia, the Blue Ridge fir, a 
new species. Castanea 1:91-94. 

Gant, R. E. 1978. The role of allelopathic interference in the 
maintenance of sourthern Appalachian heath balds. Ph. D. 
Dissertation, Univ. of Tennessee, Knoxville. 123 p. 

Gaylon, W. L. 1927. Trees and shrubs of east Tennessee. M. S. 
Thesis, Univ. of Tennessee, Knoxville. 75 p. 



254 



Gersmehl, P. J. 1969. A geographic evaluation of the ecotonal 
hypothesis of bald location in the southern Appalachians. 
Assoc. Amer. Geogr. Proc. 3:56-61. 

Gersmehl, P. J. 1973. Pseudo-timberline: the southern 
Appalachians grassy balds. Arctic and Alpine Res. 5:137- 
138. 

Glenn, L. C. 1911. Denudation and erosion in the southern 
Appalachian region and Monongahala basin. USGS f Prof. Paper 
72. 137 p. 

Golden, M. S. 1974. Forest vegetation and site relationships in 
the central portion of the Great Smoky Mountains National 
Park. Ph. D. Dissertation, Univ. of Tennessee, Knoxville. 
275 p. 

Golden, M. S. 1981. An integrated multivariate analysis of 
forest communities of the central Great Smoky Mountains. 
Amer. Midi. Nat. 106:37-53. 

Gray, A. 1842. Notes on a botanical excursion to the mountains 
of North Carolina. Amer. J. Sci. and Art 42:1-49. 

Greenback, D. 0. 1970. Climate and ecology of the balsam woolly 
aphid. Can. Entomol. 102:546-578. 

Griffin, N. C. W. 1965. Germination and early survival of 

Picea rubens Sargent in experimental laboratory and field 

plantings. M. S. Thesis, Univ. of Tennessee, Knoxville. 44 

P. 

Hardin, J. W., and C. B. MacDonald. 1975. Guide to the 
literature on plants of North Carolina. N. C. Agr. 
Extension Serv., Misc. Extension Publ. 66. 

Harmon, M. E. 1981. Fire history of Great Smoky Mountains 

National Park — 1940-1979. USDI, National Park Service, 

Southeast Regional Office, Res. /Resource Manage. Rept. 46. 
39 p. 

Harmon, M. E., S. P. Bratton, and P. S. White. 1984. 

Disturbance and vegetation response in relation to 

environmental gradients in the Great Smoky Mountains. 
Vegetatio 55:129-139. 

Harper, R. M. 1910. Summer notes on the mountain vegetation of 
Haywood County, North Carolina. Torreya 10:53-64. 

Harper, R. M. 1947. Preliminary list of southern Appalachian 
endemics. Castanea 12:100-112. 

Harper, R. M. 1948. More about southern Appalachian endemics. 
Castanea 13:124-127. 



255 



Harshberger, J. W. 1903. An ecological study of the flora of 
mountainous North Carolina. Bot. Gazette 36:241-258; 368- 
383. 

Hay, R. L. (ed.). 1980. Fraser fir and the balsam woolly aphid: 
a problem analysis. Southern Appalachian Res. /Resource 
Manage. Coop., Western Carolina Univ., Culiowhee, N.C. 26 
P. 

Hay, R. L., C. Eagar, and K. D. Johnson. 1976. Status of the 
balsam woolly aphid in the Great Smoky Mountains National 
Park. USDI , National Park Service, Southeast Region, 
Res. /Resource Manage. Rept. 20. 18 p. 

Hay, R. L., C. Eagar, and K. D. Johnson. 1978. Fraser fir in 
the Great Smoky Mountains National Park: its demise by the 
balsam woolly aphid (Adelges piceae Ratz.). Contract Rept., 
USDI, National Park Service, Southeast Regional Office, 
Atlanta, Ga. 125 p. 

Hedlund, A. and J. M. Earles. 1971. Forest statistics for east 
Tennessee Counties. USDA, Forest Service, Southeast For. 
Exp. Sta., Res. Bull. SO-26. 24 p. 

Helvey, J. D., and J. D. Hewlett. 1962. The annual range of 
soil moisture under high rainfall in the southern 
Appalachians. J. Forestry 60:485-486. 

Hickerson, T. F. 1911. The crest of the Blue Ridge Highway. J. 
Elisha Mitchell Sci. Soc. 27:160-168. 

Hoffman, H. L. 1950. Records of Picea in Virginia. Castanea 
15:55-58. 

Hoffman, H. L. 1959. Boreal forest vascular plants which are 
also native to the Great Smoky Mountains. Typescript, Univ. 
of Tennessee, Knoxville. 

Hoffman, H. L. 1964. Checklist of vascular plants of the Great 
Smoky Mountains. Castanea 29:1-45. 

Hoffman, H. L. 1966a. Notes on the vascular plant families in 
the Great Smoky Mountains. Castanea 31:301-306. 

Hoffman, H. L. 1966b. Supplement to checklist, vascular plants, 
Great Smoky Mountains. Castanea 31:307-310. 

Holmes, J. S. 1911. Forest conditions in western North 
Carolina. N. C. Geoi. and Econom. Surv. Bull. 23:1-116. 

Holt, P. C. (ed.). 1970. The distributional history of the 
oiota of the southern Appalachians, Part II: Flora. 
Virginia Polytechnic Inst, and State Univ., Blacksburg, Res. 
Division Monogr. 2. 



256 



Hopkins, A. D. 1899. Report on investigations to determine the 
cause of unhealthy conditions of the spruce and pine from 
1880-1893. West Va . Agr. Exp. Sta. Bull. 56:194-461. 

Horton, J. H., and L. H. Gaines. 1981. Floristics of selected 
heath communities along the southern section of the Blue 
Ridge Parkway. USDI , National Park Service, Southeast 
Regional Office, Res. /Resource Manage. Rept. 45. 

Huber, F. C, J. A. DeLapp, and C. A. Mitchell. 1977. Betul a 
papyrifera var. cord ifolia (Regel) Fernald in Tennessee. 
Castanea 42:324-325. 

Jacobs, B. F., C. R. Werth, and S. J. Guttman. 1984. Genetic 
relationships in Abies (fir) of eastern United States: an 
electrophoretic study. Can. J. Bot. 62:609-616. 

Jeffers, U.S., and C. F. Korstian. 1925. On the trail of the 
vanishing spruce. Sci. Monthly 20:358-368. 

Johnson, A. H., and T. G. Siccama. 1983. Acid deposition and 
forest decline. Environ. Sci. Tech. 17:294-305. 

Johnson, K. D. 1977. Balsam woolly aphid infestation of Fraser 
fir in the Great Smoky Mountains. M.S. Thesis, Univ. of 
Tennesee, Knoxville. 64 p. 

Johnson, K. D. 1980. Fraser fir and balsam woolly aphid-- 
summary information. Southern Appalachian Res. /Resource 
Manage. Coop., Western Carolina Univ., Cullowhee, N. C. 

Johnson, K. D., H. L. Lamoert, and P. J. Barry. 1980. Status 
and post-suppression evaluation of balsam woolly aphid 
infestations on Roan Mountain, Toecane Ranger District, 
Pisgah National Forest, North Carolina. USDA, Forest 
Service, S.E. State and Private For., Forest Insect and Dis. 
Manage. Rept. 80-1-13. 

Kellogg, R. S. 1907. Future of Appalachian forests. Southern 
Lumberman 53:54-55. 

Kellogg, R. S. 1910. Perpetuating the timber resources of tne 
South. American For. 16:54-55. 

King, P. B., and A. Stupka. 1950. The Great Smoky Mountains — 
their geology and natural history. Sci. Monthly 71:31-43. 

Knight, H. A., and J. P. McClure. 1966. North Carolina's 
timber. USDA, Forest Service, Southeastern For. Exp. Sta., 
Res. Bull. SE-5. 47 p. 

Knight, H. A., and J. P. McClure. 1975. North Carolina's timber 
resources, 1974. USDA, Forest Service, Southeastern For. 
Exp. Sta. Res. Rull. SE-33. 52 p. 



257 



Korstian, C. F. 1930. The southern Appalachian spruce forest as 
affected by logging and fire. USDA Tech. Bull. 1930:9-11. 

Korstian, C. F. ]937. Perpetuation of spruce on cut-over and 
burned lands in the higher southern Appalachian mountains. 
Ecol. Monogr. 7:125-167. 

Korstian, C. F. 1962. The Appalachian highland region. Pages 
178-245 in J. W. Barrett (ed.), Regional Silviculture of the 
United States. Ronald Press Co., New York. 

Kring, J. B. 1965. Vegetation succession at Craggy Gardens, 
North Carolina. M.S. Thesis, Univ. of Tennessee, Knoxville. 
61 p. 

Lambert, H. L., S. W. Morgan, and K. D. Johnson. 1980. 
Detection and evaluation of the balsam woolly adelgid 
infestations on Mt. Rogers, Virginia, 1979. USDA, Forest 
Service, State and Priv. For, For. Insect and Dis. Manage. 
Rept. 80-1-7. 

Lambert, R. S. 1961a. Logging the Great Smokies, 1880-1930. 
Tenn. Historical Quat. 20:350-363. 

Lambert, R. S. 1961b. Logging on the Little River, 1890-1940. 
East Tenn. Historical Soc . Publ. 33:32-42. 

Langdon, K. R., and J. M. Langdon. 1981. The biogeography of 
red spruce in Shenandoah National Park. Typescript ms., 
USDI, National Park Service, Shenandoah National Park, Va. 

Little, E. L., Jr. 1970. Endemic, disjunct, and northern trees 
in the southern Appalachians. In P. C. Holt (ed.), the 
distributional history of the biota of the southern 
Appalachians. Part II: Flora. Va. Polytechnic Inst, and 
State Univ., Res. Division Monogr. 2:249-290. 

Little, E. L., Jr. 1975. Rare and local conifers in the United 
States. USDA, Forest Service, Conserv. Res. Rept. 19. 

Livingston, D. and C. Mitchell. 1976. Site classification and 
mapping in the Mt . LeConte growth district. Unpubl. report, 
Great Smoky Mountains National Park Library, Gatlinburg, 
Tenn. 68 p. 

Mason, R. L., and M. H. Avery. 1931. A bibliography of the 
Great Smokies. Appalachia 18:271-277. 

McCord, D. 1968. Herringbone pattern in spruce-fir on Devil's 
Courthouse Ridge. Semester Project, Ecology 450. 
Typescript ms . , Great Smoky Mountains National Park 
Archives. 8 p. 

McCormack, J. F. 1956. Forest statistics for the mountain 
region of North Carolina, 1955. USDA, Forest Service, 



258 



Southeastern For. Exp. Sta., Forest Surv. Release 46. 46 p. 

McCracKen, R. J., R. E. Shanks, and E. E. C. Clebsch. 1962. 

Soil morphology and genesis at higher elevations of the 

Great Smoky Mountains. Soil Sci. Soc. Amer. Proc. 26:384- 
388. 

McGinnis, J. T. 1958. Forest litter and humus types of east 
Tennessee. M. S. Thesis, Univ. of Tennessee, Knoxville. 82 
P. 

McGuire, G. A. 1983. The classification and genesis of soils 
with spodic morphology in the southern Appalachians. M.S. 
Thesis, Univ. of Tennessee, Knoxville. 188 p. 

Metcalf, Z. P., and B. W. Wells. 1926. North Carolina. Pages 
412-418 in V. E. Shelford (ed.), A naturalist's guide to the 
Americas, Ecological Soc. of Amer. Baltimore. 

Miller, F. H. 1942. Vegetation type map of Great Smoky 
Mountains National Park. Unpublished document, Great Smoky 
Mountains National Park Archives, Gatlinburg, Tenn. 

Minckler, L. S. 1940a. Early planting experiments in the 
spruce-fir type of the southern Appalachians. J. Forestry 
38:651-654. 

Minckler, L. S. 1940b. Vegetative competition as related to 
plantation success in the southern Appalachian spruce type. 
J. Forestry 38:68-69. 

Minckler, L. S. 1941. Preliminary results of experiments in 
reforestation of cut-over and burned spruce lands in the 
southern Appalachians. USDA, Forest Service, Appalachian 
For. Exp. Sta., Tech. Note 47. 5 p. 

Minckler, L. S. 1943. Effect of rainfall and site factors on 
the growth and survival of young forest plantations. J. 
Forestry 41:829-833. 

Minckler, L. S. 1944. Third-year results of experiments in 
reforestation of cut-over and burned spruce lands in the 
southern Appalachians. USDA, Forest Service, Appalachian 
For. Exp. Sta., Tech. Note 60. 10 p. 

Minckler, L. S. 1945. Reforestation in the spruce type in the 
southern Appalachians. J. Forestry 43:349-356. 

Moore, B. J. 1963. A preliminary annotated checklist of the 
foliose and fruticose lichens of the Great Smoky Mountains 
National Park. M.S. Thesis, Univ. of Tennessee, Knoxville. 

Moore, T. A. 1972. The phytogeog raphy of Boone Fork sphagnum 
bog. M.S. Thesis, Appalachian State Univ., Boone, North 
Carolina. 



259 



Munn, R. F. 1961. The southern Appalachians: a bibliography 
and guide to studies. West Va . Univ. Library, Morgantown. 
106 p. 

Murphy, L. S. 1917. The red spruce: its growth and management. 
USDA, Bull. 544. 67 p. 

Nagel, W. P. 1959. Status of the balsam woolly aphid in the 
southeast in 1958 — with special references to infestations 
on Mount Mitchell, North Carolina and adjacent lands. USDA, 
Forest Service, Southeast For. Exp. Sta. Rept. 59-1. 

Nicholas, N. S. 1984. Fuel levels in forests of the Great Smoky 
Mountains National Park. M. S. Thesis, Univ. of Tennessee, 
Knoxville. 89 p. 

Nicholas, N. S. and P. S. White. In press. The effect of 
balsam woolly aphid infestation on fuel loadings in spruce- 
fir forests of Great Smoky Mountains National Park. USDI , 
National Park Service, Southeast Regional Office, 
Res. /Resource Manage. Rept. 

Nichols, R. 1977. The ecological effects of LeConte Lodge in 
the Great Smoky Mountains National Park. USDI, National 
Park Service, Uplands Field Research Lab., Gatlinburg, Tenn. 

Norris, D. H. 1964. Bryoecology of the Appalachian spruce-fir 
zone. Ph.D. Dissertation, Univ. of Tennessee, Knoxville. 
175 p. 

Oosting, H. J., and W. D. Billings. 1951. A comparison of 
virgin spruce-fir forest in the northern and southern 
Appalachian system. Ecology 32:84-103. 

Pavlovic, N. B. 1981. An examination of the seed rain and seed 
bank for evidence of seed exchange between a beech gap and a 
spruce-fir forest in the Great Smoky Mountains. M.S. 
Thesis, Univ. of Tennessee, Knoxville. 

Peet, R. K. 1979. A bibliography of the vegetation of North 
Carolina. Proc. of the 16th International Phytogeogr. 
Excursion (IPE) 1978 1:263-297. 

Peterson, C. I. 1935. The forestry work of the Civilian 
Conservation Corps in Tennessee. J. Tenn. Acad. Sci. 
10:160-166. 

Pielke, R. A. 1981. The distribution of spruce in west-central 
Virginia before logging. Castanea 46:201-216. 

Pittillo, J. D. 1976. Potential natural landmarks of the 

southern Blue Ridge portion of the Appalachians Ranges 

natural region. USDI, National Park Service, Washington, 
D.C. 372 p. 

260 



Pittillo, J. D., and T. E. Govus. 1978. A manual of important 
plant habitats of the Blue Ridge Parkway. USDI, National 
Park Service, Southeast Regional Office, Atlanta, Ga. 

Pittillo, J. D., and G. A. Smathers. 1979a. Phytogeography of 
the Balsam Mountains and Pisgah Ridge, southern Appalachian 
mountains. Proc. of the 16th International Phytogeogr. 
Excursion (IPE) 1978 1:206-245. 

Pittillo, J. D., and G. A. Smathers. 1979b. Vegetational 
patterns of the Balsam and Great Smoky Mountains of the 
southern Appalachians. Proc. Second Conf. on Sci. Res. in 
National Parks 4:307-322. 

Pluckett, L. J. 1983. Alteration of the tree growth to climate 
relationship in red spruce (Picea rubens Sarg.) Va. J. Sci. 
34:167. 

Pratt, J. H. 1905. The southern Appalachian forest reserve. J. 
Elisha Mitchell Sci. Soc. 21:156-164. 

Pratt, J. H., and J. S. Holmes. 1914. Can Mt. Mitchell's spruce 
forests be saved? N. C. Geol. and Econom. Surv. Bull. 135. 
4 p. 

Price, 0. W. 1902. Lumbering in the southern Appalachians now 
and under government ownership and supervision. Senate 
Document No. 84:61-68. 

Price, 0. W. 1905. Lumbering in the southern Appalachians. 
Forestry and Irrigation 11:469-476. 

Ramseur, G. S. 1958. The vascular flora of high mountain 
communities of the southern Appalachians. Ph.D. 
Dissertation, Univ. of North Carolina, Chapel Hill. 110 p. 

Ramseur, G. S. 1960. The vascular flora of high mountain 
communities of the southern Appalachians. J. Elisha 
Mitchell Sci. Soc. 76:82-112. 

Ramseur, G. S. 1961. A hybrid index for the mid-Appalachian 
Abies (fir or balsam). Assoc. Southeast. Biol. Bull. 8:31. 

Ramseur, G. S. 1976. Secondary succession in the spruce-fir 
forest of the Great Smoky Mountains National Park. USDI, 
National Park Service, Southeast Regional Office, 
Res. /Resource Manage. Rept. 7. 35 p. 

Rauschenberger , J. L., and H. L. Lambert. 1968. Status of the 
balsam woolly aphid on Mount Mitchell State Park. USDA, 
Forest Service, Southeast Exp. Sta., Rept. 69-1-27. 

Rauschenberger, J. L., and H. L. Lambert. 1969. Status of the 
balsam woolly aphid in the southern Appalachians--1968 . 

261 



USDA, Forest Service, Southeast Exp. Sta., Rept . 69-1-29. 

Rauschenberger , J. L., and H. L. Lambert. 1970. Status of the 
balsam woolly aphid in the southern Appaiachians--1969 . 
USDA, Forest Service, Southeast Exp. Sta. Rept. 70-1-44. 

Reed, F. W. 1905. Report on an examination of a forest tract in 
western North Carolina. U.S. Bureau of Forestry, Bull. 60. 

Rheinhardt, R. D. 1981. Vegetation of the Balsam Mountains of 
southwest Virginia. M.S. Thesis, College of William and 
Mary, Williamsburg, Va. 

Rheinhardt, R. D., and S. A. Ware. 1984. Vegetation of the 
Balsam Mountains of southwest Virginia: a phytosociological 
study. Bull. Torrey Bot . Club 111:287-300. 

Rigg, G. B., and P. D. Strausbaugh. 1949. Some stages in the 
development of sphagnum bogs in West Virginia. Castanea 
14:129-148. 

Roberts, E. V. 1940. Appalachian forest experiment station: 
major forest types of states in the region. USDA, Forest 
Service, Appalachian For. Exp. Sta. 

Roberts, E. v., and J. W. Cruikshank. 1941. The distribution of 
commercial forest trees in North Carolina. USDA, Forest 
Service, Appalachian For. Exp. Sta., For. Surv. Release 8. 
27 p. 

Robinson, J. F. 1968. Natural variation in Abies of the 
southern Appalachians. M.S. Thesis, Univ. of Tennessee, 
Knoxville. 84 p. 

Robinson, J. F., and E. Thor. 1969. Natural variation in Abies 
of the southern Appalachians. For. Sci. 15:238-245. 

Robinson, W. C. 1960. Spruce Knob revisited: a half-century of 
vegetation change. Castanea 25:53-61. 

Roller, J. H. 1942. Effect of heat and light on red spruce. 
Castanea 7:49-50. 

Rudolph, W. K. 1963. Concentrations of gamma-emitting fallout 
radionuclides from P ice a rubens and Rhododendron m aximum of 
the Great Smoky Mountains. M.S. Thesis, Univ. of Tennessee, 
Knoxville. 38 p. 

Rydberg, P. A. 1926. Botanizing in the higher Allegheny 
Mountains. J. N. Y. Bot. Garden 27:1-6. 

Sargent, R. M. 1977. Biology of the Blue Ridge. Highlands 
Biol. Foundation. Highlands, N.C. 157 p. 

Saunders, P. F. 1979. The vegetational impact of human 

262 



disturbance on the spruce-fir forests of the southern 
Appalachians. Ph.D. Dissertation, Duke Univ., Durham, N.C. 
177 p. 

Saunders, P. F., G. S. Ramseur, and G. A. Smathers. 1981. An 
ecological investigation of a spruce-fir burn in the Plott 
Balsam Mountains, North Carolina. USDI, National Park 
Service, Southeast Regional Office, Res. /Resource Manage. 
Rept. SER-48. 16 p. 

Saunders, P. F., G. A. Smathers, and G. S. Ramseur. 1983. 
Secondary succession of a spruce-fir burn in the Plott 
Balsam Mountains, North Carolina. Castanea 48:41-47. 

Scheli, E., J. C. Warden, and P. S. White. 1983. Stre ptopus 
amplexifol ius (L.) DC, new to Tennessee. Castanea 48:159. 

Schofield, W. B. 1960. The ecotone between spruce-fir and 
deciduous forest in the Great Smoky Mountains. Ph. D. 
Dissertation, Duke Univ., Durham, N. C. 176 p. 

Schwarzkopf, S. K. 1974. Comparative vegetation analysis of 
five spruce-fir areas in the southern Appalachians. Honors 
Thesis, Furman Univ., Greenville, S. C. 117 p. 

Scribner, F. L. 1889. The grasses of Roane Mountain. Bot. 
Gazette 14:253-255. 

Shanks, R. E. 1952a. Checklist of woody plants of Tennessee. 
J. Tenn. Acad. Sci. 27:27-50. 

Shanks, R. E. 1952b. Notes on woody plant distribution in 
Tennessee. Castanea 17:90-96. 

Shanks, R. E. 1954a. Climates of the Great Smoky Mountains. 
Ecology 35:354-361. 

Shanks, R. E. 1954b. Plotless sampling trials in Appalachian 
forest types. Ecology 35:237-244. 

Shanks, R. E. 1956. Altitudinal and microclimatic relationships 
of soil temperatures under natural vegetation. Ecology 
37:1-7. 

Shanks, R. E. 1958. Floristic regions of Tennessee. J. Tenn. 
Acad, of Sci. 33:195-210. 

Shanks, R. E., and E. E. C. Clebsch. 1962. Computer programs 
for the estimation of forest stand weight and mineral pool. 
Ecology 43:339-341. 

Shanks, R. E., E. E. C. Clebsch, and H. R. DeSelm. 1961. 
Estimates of standing crop and cycling rate of minerals in 
Appalachian ecosystems. Unpublished ms . , Univ. of 
Tennessee, Knoxville. 14 p. 

263 



Shanks, R. E., and J. S. Olson. 1961. First-year breakdown of 
leaf litter in southern Appalachian forests. Science 
134:194-195. 

Sharp, A. J. 1939. Taxonomic and ecological studies of eastern 
Tennessee bryophytes. Amer. Midi. Nat. 21:267-354. 

Sharp, A. J. 1957. Vascular epiphytes in the Great Smoky 
Mountains. Ecology 38:654-655. 

Sharp, A. J. 1963. Further observation on vascular epiphytes in 
the Smoky Mountains. Castanea 28:48. 

Sharp, A. J. 1970. Epilogue. In P.C. Holt (ed.), the 
distributional history of the biota of the southern 
Appalachians, Part II: Flora. Virginia Polytechnic Inst, 
and State Univ., Res. Div. Monogr. 2:405-410. 

Shelton, N. 1975. The nature of Shenandoah. Natural History 
Series, USDI, National Park Service. 110 p. 

Shields, A. R. 1962. The isolated spruce and spruce-fir forests 
of southwestern Virginia, a biotic study. Ph. D. 
Dissertation, Univ. of Tennessee, Knoxville. 174 p. 

Small, J. K, and A. A. Heller. 1892. Flora of western North 
Carolina and contiguous territory. Mem. Torrey Bot. Club 
3:1-39. 

Small, J. K., and A. M. Vail. 1893. Report of the botanical 
exploration of southwestern Virginia during the season of 
1892. Mem. Torrey Bot. Club 4:93-202. 

Smalishaw, J. 1953. Some precipitation and altitude studies of 
the Tennessee Valley Authority. Trans. Amer. Geophy. Union 
34:583-588. 

Smith, R. C. 1963. Some aspects of variation in growth and 

development of Rhododen dron maximum L. in western North 

Carolina. M. S. Thesis, North Carolina State Univ., 
Raleigh. 

Speers, C. F. 1958. The balsam woolly aphid in the southeast. 
J. Forestry 56:515-516. 

Speers, C. F. 1975. Experimental plantings in cut-over spruce- 
fir in the southern Appalachians: 50 year results. USDA, 
Forest Service, Southeastern For. Exp. Sta., Res. Note SE- 
219. 5 p. 

Stamper, P. G. 1976. Vegetation of Beech Mountain, North 
Carolina. M. S. Thesis, Univ. of Tennessee, Knoxville. d 
185 p. 



264 



Stephens, L. A. 1969. A comparison of climatic elements at four 
elevations in the Great Smoky Mountains National Park. M. 
S. Thesis, Univ. of Tennessee, Knoxville. 119 p. 

Stephenson, S. L., and S. Adams. 1984. The spruce-fir forest on 
the summit of Mt. Rogers in southwest Virginia. Bull. Torr. 
Bot. Club 111:69-75. 

Stephenson, S. L., and J. F. Clovis. 1983. Spruce forests of 
the Allegheny Mountains in central West Virginia. Castanea 
48:1-12. 

Stevens, C. E. 1968. A remarkable disjunct occurrence of Cornus 
c anadensis in the Virginia Blue Ridge. Castanea 33:247- 
248. 

Stevenson, S. L., and H. S. Adams. 1984. The spruce-fir forest 
on the summit of Mount Rogers in southwest Virginia. Bull. 
Torrey Bot. Club 111:69-75. 

Stockbridge, H. E. 1911. A bibliography of southern Appalachian 
and White Mountain Regions. Proc. Soc. Amer. For. 6:173- 
254. 

Strausbaugh, P. D. 1934. Cranberry Glades. Amer. For. 40:362- 
364, 382-383. 

Stupka, A. 1938. Report on progress made in a survey of the 
natural history of the Great Smoky Mountains National Park. 
J. Tenn. Acad. Sci. 13:60-62. 

Stupka, A. 1964. Trees, shrubs, and woody vines of the Great 
Smoky Mountains National Park. Univ. of Tennessee Press, 
Knoxville. 186 p. 

Sudworth, G. B., and J. B. Killebrew. 1897. The forests of 
Tennessee: their extent, character and distribution. Tenn. 
Industr. League. M.E. Church, Nashville, Tenn. 32 p. 

Sullivan, J. H., J. D. Pittillo, and G. D. Smathers. 1980. 
Dispersal and establishment of red spruce and Fraser fir in 
three bald areas of the southern Appalachians. USDI , 
National Park Service, Southeast Regional Office, 
Res. /Resource Manage. Rept. 

Tanner, J. C. 1963. Mountain temperatures in the southeastern 
and southwestern United States during late spring and early 
summer. J. App. Meteor. 2:473-483. 

Thomas, R. B. 1982. Invasion of beech into a high elevation 
heath bald at Craggy Gardens, North Carolina. M.S. Thesis, 
Western Carolina Univ., Cullowhee, N.C. 57 p. 

Thor, E. 1966. Christmas tree research in Tennessee. Amer. 
Christmas Tree Journal 10(3):7-12. 



265 



Thor, E. f and P. E. Barnett. 1974. Taxonomy of Abies in the 
southern Appalachians: variations in balsam monoterpenes 
and wood properties. For. Sci. 20:32-40. 

Tucker, G. E. 1972. The vascular flora of Bluff Mountain, Ashe 
County, North Carolina. Castanea 37:2-26. 

USDA, Forest Service. 1947. Bibliography of the Appalachian 
Forest Experiment Station, 1921-1946. Southeast. For. Exp. 
Sta., Asheville, N.C. 192 p. 

Wahlenberg, W. G. 1951. Planting in the Appalachian spruce-fir 
type. J. Forestry 49:569-571. 

Walker, L. C. 1964. Humus types of the Highlands area of North 
Carolina. J. Elisha Mitchell Sci. Soc. 80:24-29. 

Ward, D. B. 1962. The first record of Fraser fir. Castanea 
27:78-79. 

Ward, J. D. 1974. Status of balsam woolly aphid, Adelge s 
piceae, on Roan Mountain, Toecone Ranger District, Pisgah 
National Forest, N. C. — 1974. USDA, Forest Service, State 
and Priv. For., Div. of For. Pest Manage., Asheville, N.C, 
Rept. 74-1-3. 11 p. 

Ward, J. D., E. T. Wilson, and W. M. McDonell. 1973. Status of 
the balsam woolly aphid, Adelges piceae (Ratz.), in the 
southern Appalachians — 1972. USDA, Forest Service, Div. 
For. Pest Manage., Asheville, N. C, Rept. 73-1-35. 

Weaver, G. T. 1972. Dry matter and nutrient dynamics in red 
spruce-Fraser fir and yellow birch ecosystems in the Balsam 
Mountains, Western North Carolina. Ph. D. Dissertation, 
Univ. of Tennessee, Knoxville. 406 p. 

Weaver, G. T., and H. R. DeSelm. 1973. Biomass distributional 
patterns in adjacent coniferous and deciduous forest 
ecosystems. Proc. of the Working Party on Forest Biomass, 
IUFRO, Univ. of Maine Press, 413-427. 

Wells, B. W. 1924. Major plant communities of North Carolina. 
N. C. Agr. Exp. Sta., Tech. Bull. 25:1-20. 

Westveld, M. 1953. The ecology and silviculture of spruce-fir 
forests of eastern North America. J. Forestry 51:422-430. 

Whigham, D. F. 1969. Vegetation patterns on the north slopes of 
Bluff Mountain, Ashe County, North Carolina. J. Elisha 
Mitchell Sci. Soc. 85:1-15. 

White, E. 1939. Plants of the Smoky Mountains. Trans. 111. 
Acad. Sci. 32:82-85. 



266 



White, P. S. 1982. The flora of Great Smoky Mountains National 
Park: an annotated checklist of the the vascular plants and 
a review of previous floristic work. USDI, National Park 
Service, ^Southeast Regional Office, Res. /Resource Manage. 

White, P. S M. D. MacKenzie, and R. T. Busing, in press. 
Natural disturbance and gap phase dynamics in southern 
Appalachian spruce-fir forests, USA. Can. J. For. Res. 

White, P. S., R. i. Miller, and G. S. Ramseur. 1984. The 
species-area relationship of the southern Appalachian hiqh 
peaks: vascular plant richness and rare plant 
distributions. Castanea 49:47-61. 

White, P. s., and B. E. Wofford. 1984. Rare native Tennessee 
vascular plants in the flora of Great Smoky Mountains 
National Park. J. Tenn. Acad. Sci. 59:61-64. 

Whittaker, R. H. 1948. A vegetation analysis of the Great Smoky 
Mountains. Ph. D. Dissertation, Univ. of Illinois, Urbana. 
478 p. 

Whittaker, R. H. 1956. Vegetation of the Great Smoky Mountains. 
Ecol. Monogr. 26:1-80. 

Whittaker, R. H. 1961. Estimation of net primary produciton of 
forest and shrub communities. Ecology 47:177-180. 

Whittaker, R. H. 1962. Net production relations of shrubs in 
the Great Smoky Mountains. Ecology 43:357-377. 

Whittaker, R. H. 1963. Net production of heath balds and forest 
heaths in the Great Smoky Mountains. Ecology 44:176-182. 

Whittaker, R. H. 1965. Branch dimensions and estimation of 
branch production. Ecology 46:365-370. 

Whittaker, R. H. 1966. Forest dimensions and production in the 
Great Smoky Mountains. Ecology 47:103-121. 

Whittaker, R. h and V. Garfme. 1962. Leaf characteristics 
f, chlorophyll in relation to exposure and production in 
RhPdpdendrpn maximum. Ecology 43:120-125. 

Whittaker, R. H., and G. M. Woodwell. 1967. Surface area 
relations of woody plants and forest communities. Amer. J. 
Bot. 54:931-939. 

wieder, R. K, A. M. McCormick, and G. E. Lang. 1981. Vegetation 
analysis of Big Run Bog, a nonglaciated Sphagnum bog in West 
Virginia. Castanea 46:16-29. 

Wlihe Jf' "• J y k J f- 19 ™- The Blue Ridge: man and nature in 
the Shenandoah National Park and Blue Ridge Parkway. Univ. 



Qg-7 



of Virginia Press, Charlottesville. 103 p. 

Wolfe, J. A. 1967. Forest soil characterization as influenced 
by vegetation and bedrock in the spruce-fir zone of the 
Great Smoky Mountains. Ph. D. Dissertation, Univ. of 
Tennessee, Knoxville. 193 p. 

zavarin, E., and K. Snajberk. 1972. Geographical variability of 
monoterpenes from Abies balsamea and A_* f ras eri . Phytochem. 
11:1407-1421. 



Cop V 



581.5 3416 

W White 

Cop 1, The Southern Appalachian 
spruce-fir ecosystem. . . 



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